HttpURLConnectionconnection = (HttpURLConnection) URL.openConnection();
connection.setRequestMethod("POST");
// using xml
connection.setRequestProperty("Content-Type", "application/xml");
connection.setDoOutput(true);
BufferedWriter bw = new BufferedWriter(
        new OutputStreamWriter(connection.getOutputStream()));
bw.write(body);
bw.flush();
bw.close();

// response http code
int responseCode = connection.getResponseCode();
if (responseCode == 400) {
    System.out.println("400 ERROR");
} else if (responseCode == 500) {
    System.out.println("500 ERROR");
} else {
    System.out.println("200 SUCCESS");
}
connection.getInputStream() // 응답 body