public static void main(String[] args) throws Exception {
    sendPost();
}

private static void sendPost() throws Exception {

    String url = "https://exampleSite.com";
    URL obj = new URL(url);
    HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();

    String account = "acc";
    String password = "pass";

    //add reuqest header
    con.setRequestMethod("POST");
    con.setRequestProperty("Content-type", "text/xml");
    String urlParameters = "account=" + account + "&password=" + password;

    // Send post request
    con.setDoOutput(true);
    DataOutputStream wr = new DataOutputStream(con.getOutputStream());
    wr.writeBytes(urlParameters);
    wr.flush();
    wr.close();

    int responseCode = con.getResponseCode();
    System.out.println("nSending 'POST' request to URL : " + url);
    System.out.println("Post parameters : " + urlParameters);
    System.out.println("Response Code : " + responseCode);

    BufferedReader in = new BufferedReader(
            new InputStreamReader(con.getInputStream()));
    String inputLine;
    StringBuffer response = new StringBuffer();

    while ((inputLine = in.readLine()) != null) {
        response.append(inputLine);
    }
    in.close();

    //print result
    System.out.println(response.toString());

}