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From Grandl Robert <rgra...@yahoo.com>
Subject Reducer - getMapOutput
Date Mon, 30 Jul 2012 16:10:57 GMT

I am trying to modify the code for data transfer of intermediate output. 

In this respect, on the reduce side in getMapOuput I want to have the connection with the
TaskTracker(setupSecureConnection), but then on doGet the TaskTracker to be able to delay
the response back to the client. I tried with Thread.sleep(time), before setting up the response.setHeader(FROM_MAP_TASK,
mapId) and the subsequent headers/content. But it seems the reducer will continue to read
the headers immediately and get NULL.

Do you know how can I do the reducer to wait for TaskTracker to update this information before
reading it. I tried with a while loop and reading the connection.getHeaderField(...) till
not null but seems it always remains in the loop :(.

Probably is more a HttpServlet related problem but I am not very familiar with that. 

Do you have any idea how can I do it ?


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