String token = "_token="+(String) data.get("_token");
String username = "username="+(String) data.get("username");
String password = "password="+(String) data.get("password");
String together = token+", "+password+", "+username;
String encodedData = URLEncoder.encode(together, "UTF-8" );
con = (HttpURLConnection) u.openConnection();
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", "Mozilla/5.0");
con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
con.setRequestProperty("Content-Length", String.valueOf(encodedData.length()));


OutputStream os = con.getOutputStream();
os.write(encodedData.getBytes());