It would very helpful if someone can point to where I can possibly find a solution to this problem.
Thanks. Vivek -- On Tue, Sep 13, 2011 at 12:27 PM, Vivek K <[email protected]> wrote: > Hi all, > > I am trying to build a Hadoop/MR application in c++ using hadoop-pipes. I > have been able to successfully work with my own mappers and reducers, but > now I need to generate output (from reducer) in a format different from the > default TextOutputFormat. I have a few questions: > > (1) Similar to Hadoop streaming, is there an option to set OutputFormat in > HadoopPipes (in order to use say org.apache.hadoop.io.SequenceFile.Writer) ? > I am using Hadoop version 0.20.2. > > (2) For a simple test on how to use an in-built non-default writer, I tried > the following: > > hadoop pipes -D hadoop.pipes.java.recordreader=true -D > hadoop.pipes.java.recordwriter=false -input input.seq -output output > -inputformat org.apache.hadoop.mapred.SequenceFileInputFormat -writer > org.apache.hadoop.io.SequenceFile.Writer -program my_test_program > > However this fails with a ClassNotFound exception. And if I remove the > -writer flag and use the default writer, it works just fine. > > (3) Is there some example or discussion related to how to write your own > RecordWriter and run it with Hadoop-pipes ? > > Thanks. > > Best, > Vivek > -- > >
