@Override
    public void seek(final long pos) throws IOException {
        position = pos;
        if (raFile != null) {
            raFile.position(pos);
            streamAdaptor.recycle(Channels.newInputStream(raFile));
        }
    }
@param b   to fill
@param off offset
@param len length
stroom-data/stroom-data-store-impl-fs/src/main/java/stroom/data/store/impl/fs/UncompressedInputStream.java