ByteBuffer-based read API for pread

[lei liu]

 There is ByteBuffer read API for sequential read in CDH4.3.1,
example:public synchronized int read(final ByteBuffer buf) throws
IOException  API. But there is not ByteBuffe read API for pread.

Why don't support ByteBuffer read API for pread in CDH4.3.1?

Thanks,

LiuLei