how to deserialize the contents of hadoop output (sequencefileoutputformat)

[Lin Guo <gu...@yahoo.com>]

I am wondering whether it is possible to deserialize the keys and values in a hadoop output file where the output format is SequenceFileOutputFormat. 

many thanks!



      

Re: how to deserialize the contents of hadoop output (sequencefileoutputformat)

[Stuart Sierra <ma...@stuartsierra.com>]

On Tue, Jun 3, 2008 at 6:17 AM, Lin Guo <gu...@yahoo.com> wrote:
> I am wondering whether it is possible to deserialize the keys and values in a hadoop output file where the output format is SequenceFileOutputFormat.

I wrote some code to do this, samples attached.
-Stuart

RE: how to deserialize the contents of hadoop output (sequencefileoutputformat)

["Chen, Young" <yo...@intel.com>]

Do you mean read output file which create by SequenceFile.createWriter? If so, maybe below code part will be useful. It reads out long integer number out from sequence file.

      SequenceFile.Reader reader = new SequenceFile.Reader(fileSys, inFile, jobConf);
      LongWritable numInside = new LongWritable();
      LongWritable numOutside = new LongWritable();
      reader.next(numInside, numOutside);

-----Original Message-----
From: Lin Guo [mailto:guolin2001@yahoo.com] 
Sent: 2008年6月3日 18:17
To: core-user@hadoop.apache.org
Subject: how to deserialize the contents of hadoop output (sequencefileoutputformat)

I am wondering whether it is possible to deserialize the keys and values in a hadoop output file where the output format is SequenceFileOutputFormat. 

many thanks!



      

Re: how to deserialize the contents of hadoop output (sequencefileoutputformat)

[Chris Douglas <ch...@yahoo-inc.com>]

If your keys and values have meaningful toString methods, hadoop fs - 
text <path> will print the contents to stdout. -C

On Jun 3, 2008, at 3:17 AM, Lin Guo wrote:

> I am wondering whether it is possible to deserialize the keys and  
> values in a hadoop output file where the output format is  
> SequenceFileOutputFormat.
>
> many thanks!
>
>
>