final private ByteBuffer readFromFile(final long offset,final int length){
  try {
    final ByteBuffer dst=ByteBuffer.allocate(length);
    FileChannelUtility.readAll(opener,dst,offset);
    dst.flip();
    return dst;
  }
 catch (  IOException ex) {
    throw new RuntimeException(ex);
  }
}

final private ByteBuffer readFromFile ( final long offset , final int length ) { try { final ByteBuffer dst = ByteBuffer . allocate ( length ) ; FileChannelUtility . readAll ( opener , dst , offset ) ; dst . flip ( ) ; return dst ; } catch ( IOException ex ) { throw new RuntimeException ( ex ) ; } }
read the record from the file .
