hadoop-common-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Owen O'Malley <omal...@apache.org>
Subject Re: Output.collect uses toString for custom key class. Is it possible to change this?
Date Tue, 16 Dec 2008 17:22:47 GMT

On Dec 16, 2008, at 8:58 AM, David Coe wrote:
> Thank you for your swift response.  I am getting this error when I try
> your suggestion:
> java.lang.NullPointerException
>    at
> org.apache.hadoop.io.SequenceFile$Writer.append(SequenceFile.java:987)

It means you are trying to write a null value. Your reduce is doing  
something like:

output.collect(key, null);

In TextOutputFormat, that is ok and just skips it.  
SequenceFileOutputFormat doesn't like nulls.

-- Owen

View raw message