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AW: Output of MAP Class only
Hi Rajen,

you can write stuff to the task attempt directory and it will be included in the output of your MapReduce job.

You can get the directory from the Mapper context:


In that path, you can just open new files via the FileSystem methods.

Hope that helps,

-----Urspr√ľngliche Nachricht-----
Von: Rajen Bhatt (RBEI/EST1) [mailto:[EMAIL PROTECTED]]
Gesendet: Freitag, 30. September 2011 12:47
Betreff: Output of MAP Class only

Dear Experts:
We are scaling down an image to few partitions and processing each partition in the MAP class. We want to save the output of MAP class only to demonstrate and present how this output sub images are looking like. Can somebody give us a hint on how to only save the output of MAP class (before we send them to the REDUCER class) ? We want to demonstrate to the students the process of MAP REDUCE flow on simple image processing operation. We are doing the attached images operation using MAP REDUCE. We are sending the original image and getting as an output the edge detected image. First one is the input Image, we are splitting it, performing the edge detection on each split, and then merging in the reducer.
Thanks and Regards,
Dr. Rajen Bhatt
(Corporate Research @ Robert Bosch, India)
Off: +91-80-4191-2025
Mob: +91-9901241005