try {
    // Create a URLConnection object for a URL
    URL url = new URL("http://hostname:80");
    URLConnection conn = url.openConnection();

    // List all the response headers from the server.
    // Note: The first call to getHeaderFieldKey() will implicit send
    // the HTTP request to the server.
    for (int i=0; ; i++) {
        String headerName = conn.getHeaderFieldKey(i);
        String headerValue = conn.getHeaderField(i);

        if (headerName == null && headerValue == null) {
            // No more headers
            break;
        }
        if (headerName == null) {
            // The header value contains the server's HTTP version
        }
    }
} catch (Exception e) {
}