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From Piyush Kansal <piyush.kan...@gmail.com>
Subject Re: Query regarding Hadoop version 0.20.203
Date Mon, 05 Mar 2012 14:03:36 GMT
Harsh,

When I trying to readFields as follows:

FileStatus origFStatus[] = ipFs.listStatus( ip );
DataInput dataIp;
origFStatus[ 0 ].readFields( dataIp );

I am getting a compilation error "variable dataIp might not have been
initialized".

How do we initialize it? Is there a direct method by which I can get the
read the fields easily.

On Mon, Mar 5, 2012 at 7:49 AM, Piyush Kansal <piyush.kansal@gmail.com>wrote:

> Thanks Harsh. It worked.
>
>
> On Mon, Mar 5, 2012 at 5:58 AM, Harsh J <harsh@cloudera.com> wrote:
>
>> Piyush,
>>
>> On Mon, Mar 5, 2012 at 3:16 PM, Piyush Kansal <piyush.kansal@gmail.com>
>> wrote:
>> > Ques 1:
>> > ======
>> > I have a HDFS directory which contains the o/p files of reducer. I want
>> to
>> > read all the part-r-* files present in this directory.
>> >
>> > I have already tried following options as follows but no luck:
>> > - FileSystem.listStatus
>> >
>> > Can you please suggest how can I do it?
>>
>> Iterate over the FileStatus objects returned by listStatus (they'll be
>> in the right order), and read them one by one. Does that not work for
>> you?
>>
>> > Ques 2:
>> > ======
>> > Since MultipleOutputs/MultipleOutputFormat is not there in 0.20.203, so
>> can
>> > we achieve the same functionality provided by these classes.
>>
>> Upgrade to either 1.0.1 to get MultipleOutputs for new API (Was only
>> recently released with that backport from 0.21), or to any alternative
>> distributions that offer it back-ported, or perhaps switch back to
>> using the stable (old) API which is still recommended to use for MR.
>>
>> Alternatively, read
>>
>> http://wiki.apache.org/hadoop/FAQ#Can_I_write_create.2BAC8-write-to_hdfs_files_directly_from_map.2BAC8-reduce_tasks.3F
>>
>> --
>> Harsh J
>>
>
>
>
> --
> Regards,
> Piyush Kansal
>
>


-- 
Regards,
Piyush Kansal

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