getDNS server

private static String getDNSServer() {
    ConnectivityManager connectivityManager = (ConnectivityManager) mContext.getSystemService(mContext.CONNECTIVITY_SERVICE);
    for(Network network :connectivityManager.getAllNetworks())
    {
        NetworkInfo networkInfo = connectivityManager.getNetworkInfo(network);
        if (networkInfo.isConnected()) {
            LinkProperties linkProperties = connectivityManager.getLinkProperties(network);
            return linkProperties.getDnsServers().toString();
        }
    }
    //Failed
    return "127.0.0.1";
}