return fileChannel.map(MapMode.READ_ONLY, size, offset);
return fileChannel.map(MapMode.READ_ONLY, offset, size);
    public MappedByteBuffer getRegion(Integer size, Long offset)        throws IOException    {        FileChannel fileChannel = getFileChannel(true);                /* fileChannel should not be "null" as it will throw an exception if         * there happens to be an error.         */                return fileChannel.map(MapMode.READ_ONLY, size, offset);    }