Why ScannerTimeoutException is not handled in TableInputFormat?

[Jan Lukavský]

Hi all,

patch to HBASE-4269 removed handling of ScannerTimeoutException from 
TableRecordReader. Is there a reason for this? We are now seeing a lot 
of ScannerTimeoutExceptions in our jobs, which were previously handled. 
The problem is caused by ScannerTimeoutException being derived from 
DoNotRetryIOException (why's that?). Would it be safe to just derive 
this exception from IOException? And if not, should the 
TableRecordReader explictly handle this exception? The same problem may 
arise with LeaseException, which is also derived from 
DoNotRetryIOException. Both of these exception may have the same cause 
and in my understanding can be handled in the RecordReader without any 
harm. Or am I wrong?

Thanks for answer,
 Jan