byte[] buffer = new byte[4096];
RegionFile region = RegionFileCache.getRegionFile(baseFolder, x, z);
try {
    DataInputStream istream = new DataInputStream(new GZIPInputStream(new FileInputStream(chunkFile)));

    DataOutputStream out = region.getChunkDataOutputStream(x & 31, z & 31);

    int length = 0;
    while ((length = istream.read(buffer)) != -1) {
        out.write(buffer, 0, length);
    }

    out.close();
    istream.close();
} catch (IOException e) {
    e.printStackTrace();
}