Re: Question on BytesWritable

[John Meagher]

https://issues.apache.org/jira/browse/HADOOP-6298

On Tue, Oct 1, 2013 at 12:39 AM, Chandra Mohan, Ananda Vel Murugan
ananda.muru...@honeywell.com wrote:
 Hi,



 I am using Hadoop 1.0.2. I have written a map reduce job. I have a
 requirement to process the whole file without splitting. So I have written a
 new input format to process the file as a whole by overriding the
 isSplittable() method. I have also created a new Record reader
 implementation to read the whole file. I followed the sample in Chapter 7 of
 “Hadoop- The Definitive Guide” book. In my map reduce job, my mapper emits
 BytesWritable as value. I want to get the bytes and read some specific
 information from the bytes. I use ByteArrayInputStream and do further
 processing. But strangely the following code shows different numbers.
 Because of this I am getting errors.



 //value - BytesWritable

 System.out.println(“Bytes length ” + value.getLength()); // Bytes length
 1931650

 byte[] bytes = value.getBytes();

 System.out.println(Bytes array length+bytes.length); //Bytes array length
 2897340



 My file size is 1931650 bytes. I don’t know why byte array is bigger than
 the original file.



 Any idea what is going wrong. Please help. Thanks in advance.



 Regards,

 Anand.C

Question on BytesWritable

[Chandra Mohan, Ananda Vel Murugan]

Hi,

I am using Hadoop 1.0.2. I have written a map reduce job. I have a requirement 
to process the whole file without splitting. So I have written a new input 
format to process the file as a whole by overriding the isSplittable() method. 
I have also created a new Record reader implementation to read the whole file. 
I followed the sample in Chapter 7 of Hadoop- The Definitive Guide book. In 
my map reduce job, my mapper emits BytesWritable as value. I want to get the 
bytes and read some specific information from the bytes. I use 
ByteArrayInputStream and do further processing. But strangely the following 
code shows different numbers. Because of this I am getting errors.

//value - BytesWritable
System.out.println(Bytes length  + value.getLength()); // Bytes length 1931650
byte[] bytes = value.getBytes();
System.out.println(Bytes array length+bytes.length); //Bytes array length 
2897340

My file size is 1931650 bytes. I don't know why byte array is bigger than the 
original file.

Any idea what is going wrong. Please help. Thanks in advance.

Regards,
Anand.C