What is the best way of reading/writing binary input/output files with MapReduce?

In all samples I've seen so far, mapreduce apps take text files as input and write text as output.

I'd like my app to 开发者_开发知识库read objects from the binary file and write objects back to output file.

What is the best way to do that in MapReduce?

I'm writing the app in java

SequenceFile provides a persistent data structure for binary key-value pairs. You can find more information in the below URL.

http://wiki.apache.org/hadoop/SequenceFile

http://hadoop.apache.org/common/docs/current/api/org/apache/hadoop/io/SequenceFile.html