Android HTTPURLConnection auto read gzip inputStream

TransprentHTTPGzipedStreamReader.java

public static String networkInputstreamtoString(InputStream is) throws IOException {
    byte []sig = new byte[2];
    final PushbackInputStream pb = new PushbackInputStream(is, sig.length);
    pb.read(sig);
    pb.unread(sig);
    if (sig[0] == (byte) 0x1f && sig[1] == (byte) 0x8b) {
        is = new GZIPInputStream(pb);
    } else {
        is = new BufferedInputStream(pb);
    }

    int len;
    byte buffer[] = new byte[1024];
    final StringBuilder sb = new StringBuilder();
    try {
        while ((len = is.read(buffer)) != -1) {
            sb.append(new String(buffer, 0, len, "UTF-8"));
        }
        return sb.toString();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}