Re: Anything like RandomAccessFile in Hadoop FS ?

2008-11-13 Thread Dhruba Borthakur
One can open a file and then seek to an offset and then start reading
from there. For writing, one can write only to the end of an existing
file using FileSystem.append().

hope this helps,
dhruba

On Thu, Nov 13, 2008 at 1:24 PM, Tsz Wo (Nicholas), Sze
<[EMAIL PROTECTED]> wrote:
> Append is going to be available in 0.19 (not yet released).  There are new 
> FileSystem APIs for append, e.g.
>
> //FileSysetm.java
>  public abstract FSDataOutputStream append(Path f, int bufferSize,
>  Progressable progress) throws IOException;
>
> Nicholas Sze
>
>
>
>
> - Original Message 
>> From: Bryan Duxbury <[EMAIL PROTECTED]>
>> To: Wasim Bari <[EMAIL PROTECTED]>
>> Cc: [EMAIL PROTECTED]
>> Sent: Thursday, November 13, 2008 1:11:57 PM
>> Subject: Re: Anything like RandomAccessFile in Hadoop FS ?
>>
>> I'm not sure off hand. Maybe someone else can point you in the right 
>> direction?
>>
>> On Nov 13, 2008, at 1:09 PM, Wasim Bari wrote:
>>
>> > Hi,
>> >Thanks for reply.
>> >
>> > HDFS supports append file. How can I do this ?
>> > I tried to look API under fileSystem create method but couldn't find.
>> >
>> > Thanks for ur help.
>> >
>> > Wasim
>> >
>> > --
>> > From: "Bryan Duxbury"
>> > Sent: Thursday, November 13, 2008 9:48 PM
>> > To:
>> > Subject: Re: Anything like RandomAccessFile in Hadoop FS ?
>> >
>> >> If you mean a file where you can write anywhere, then no. HDFS is  
>> >> streaming
>> only. If you want to read from anywhere, then no problem -  just use seek() 
>> and
>> then read.
>> >> On Nov 13, 2008, at 11:40 AM, Wasim Bari wrote:
>> >>> Hi,
>> >>>  Is there any Utility for Hadoop files which can work same as
>> RandomAccessFile in Java ?
>> >>> Thanks,
>> >>>
>> >>> Wasim
>
>


Re: Anything like RandomAccessFile in Hadoop FS ?

2008-11-13 Thread Tsz Wo (Nicholas), Sze
Append is going to be available in 0.19 (not yet released).  There are new 
FileSystem APIs for append, e.g.

//FileSysetm.java
  public abstract FSDataOutputStream append(Path f, int bufferSize,
  Progressable progress) throws IOException;

Nicholas Sze




- Original Message 
> From: Bryan Duxbury <[EMAIL PROTECTED]>
> To: Wasim Bari <[EMAIL PROTECTED]>
> Cc: [EMAIL PROTECTED]
> Sent: Thursday, November 13, 2008 1:11:57 PM
> Subject: Re: Anything like RandomAccessFile in Hadoop FS ?
> 
> I'm not sure off hand. Maybe someone else can point you in the right 
> direction?
> 
> On Nov 13, 2008, at 1:09 PM, Wasim Bari wrote:
> 
> > Hi,
> >Thanks for reply.
> > 
> > HDFS supports append file. How can I do this ?
> > I tried to look API under fileSystem create method but couldn't find.
> > 
> > Thanks for ur help.
> > 
> > Wasim
> > 
> > ------
> > From: "Bryan Duxbury" 
> > Sent: Thursday, November 13, 2008 9:48 PM
> > To: 
> > Subject: Re: Anything like RandomAccessFile in Hadoop FS ?
> > 
> >> If you mean a file where you can write anywhere, then no. HDFS is  
> >> streaming 
> only. If you want to read from anywhere, then no problem -  just use seek() 
> and 
> then read.
> >> On Nov 13, 2008, at 11:40 AM, Wasim Bari wrote:
> >>> Hi,
> >>>  Is there any Utility for Hadoop files which can work same as  
> RandomAccessFile in Java ?
> >>> Thanks,
> >>> 
> >>> Wasim



Re: Anything like RandomAccessFile in Hadoop FS ?

2008-11-13 Thread Bryan Duxbury
I'm not sure off hand. Maybe someone else can point you in the right  
direction?


On Nov 13, 2008, at 1:09 PM, Wasim Bari wrote:


Hi,
   Thanks for reply.

HDFS supports append file. How can I do this ?
I tried to look API under fileSystem create method but couldn't find.

Thanks for ur help.

Wasim

--
From: "Bryan Duxbury" <[EMAIL PROTECTED]>
Sent: Thursday, November 13, 2008 9:48 PM
To: 
Subject: Re: Anything like RandomAccessFile in Hadoop FS ?

If you mean a file where you can write anywhere, then no. HDFS is   
streaming only. If you want to read from anywhere, then no problem  
-  just use seek() and then read.

On Nov 13, 2008, at 11:40 AM, Wasim Bari wrote:

Hi,
 Is there any Utility for Hadoop files which can work same  
as  RandomAccessFile in Java ?

Thanks,

Wasim




Re: Anything like RandomAccessFile in Hadoop FS ?

2008-11-13 Thread Bryan Duxbury
If you mean a file where you can write anywhere, then no. HDFS is  
streaming only. If you want to read from anywhere, then no problem -  
just use seek() and then read.


On Nov 13, 2008, at 11:40 AM, Wasim Bari wrote:


Hi,
 Is there any Utility for Hadoop files which can work same as  
RandomAccessFile in Java ?

Thanks,

Wasim




Anything like RandomAccessFile in Hadoop FS ?

2008-11-13 Thread Wasim Bari
Hi,
 Is there any Utility for Hadoop files which can work same as 
RandomAccessFile in Java ? 
Thanks,

Wasim