> From the java code which creates the sequence file, it has set the key
>class to NullWritable.class:
> job.setOutputKeyClass(org.apache.hadoop.io.NullWritable.class);
...
> I think that caused the mismatch:
> wrong key class: org.apache.hadoop.io.BytesWritable is not class
>org.apache.hadoop.io.NullWritable
In all possibilities, the exception you¹re hitting originates from here
https://github.com/apache/hadoop/blob/trunk/hadoop-common-project/hadoop-co
mmon/src/main/java/org/apache/hadoop/io/SequenceFile.java#L2328
> Anyone knows why Tez will check the key and value class when doing sort
>stuff?
As I said in my earlier mail, if you can check the SequenceFile headers
and they look like my pasted pair, then we know it¹s the same as the known
issue.
Cheers,
Gopal
