Hi Anh, How about using ChainMapper? Is the helpful for you? http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapred/lib/ChainMapper.html
Thanks, Tsuyoshi On Wed, Oct 16, 2013 at 1:16 AM, Anh Pham <[email protected]> wrote: > (Please correct me if I am wrong) So the original chain is: > InputSplits-->Mapper--> [Sorting/Shuffling, etc]-->Reducer-->... > > Now I don't want the input splits to get to the Mappers first, but to go to > some other new stage instead (we can call it Pre-Mapper for example, this > class will be created by myself). > > So the new order will be: InputSplits -> Pre-Mapper->Mapper ->... > > I'm currently reading the source code. However, I still cannot find any > clue (what classes I should touch). Any suggestion is welcome. Thank you > very much :) -- - Tsuyoshi
