@RestController
@RequestMapping(value = "/students")
public class AtheniumController {

    private final AtheniumServiceImpl service;

    @Autowired
    public AtheniumController(AtheniumServiceImpl service) {
        this.service = service;
    }

    @RequestMapping("/student/{studentSurname}/{studentName}/{studentPatronymic}/{studentNumber}")
    @ResponseBody
    public String checkLogin(@PathVariable(value = "studentSurname") String studentSurname,
                             @PathVariable(value = "studentName") String studentName,
                             @PathVariable(value = "studentPatronymic") String studentPatronymic,
                             @PathVariable(value = "studentNumber") String studentNumber) {

        Student lvStudent = new Student(studentSurname, studentName, studentPatronymic, Long.valueOf(studentNumber));
        if (service.checkLogin(lvStudent)) {
            return "OK";
        } else {
            return "Проверьте введенные данные! (Также возможна проблема в серверах ДГУ)";
        }
    }

    @RequestMapping(value = "marks", method = RequestMethod.GET)
    @ResponseBody
    public List<Mark> getMarks() {
        return service.getMarks();
    }

    @RequestMapping(value = "marks/{id}", method = RequestMethod.DELETE)
    @ResponseBody
    public void delete(@PathVariable long id) {
        service.remove(id);
    }
}

public class RequestRegister extends AsyncTask<Student, Void, String> {
    BufferedOutputStream bos;

    @Override
    protected String doInBackground(Student... pStudents) {

        try {
            URL url = null;
            try {
                url = new URL(Constants.POST_STUDENT);
            } catch (MalformedURLException pE) {
                pE.printStackTrace();
            }
            HttpURLConnection urlConnection = null;
            try {
                assert url != null;
                urlConnection = (HttpURLConnection) url.openConnection();
            } catch (IOException pE) {
                pE.printStackTrace();
            }
            assert urlConnection != null;
            urlConnection.setRequestProperty("Content-Type", "application/json");
            urlConnection.setRequestMethod("POST");
            urlConnection.setDoInput(true);
            urlConnection.setDoOutput(true);
            urlConnection.connect();

            JSONObject jo = new JSONObject();

            jo.put("studentSurname", pStudents[0].getStudentSurname());
            jo.put("studentName", pStudents[0].getStudentName());
            jo.put("studentPatronymic", pStudents[0].getStudentPatronymic());
            jo.put("studentNumber", pStudents[0].getStudentNumber());

            bos = new BufferedOutputStream(urlConnection.getOutputStream());
            bos.write(jo.toString().getBytes());

            String result = urlConnection.getResponseMessage();

        } catch (JSONException | IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bos.flush(); //очищает поток output-a
                bos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            //urlConnection.disconnect();
        }
        //return null;

        return null;
    }

@RequestMapping(value = "/student", method = RequestMethod.POST)
@ResponseBody
public String checkLogin(@RequestParam(value = "studentSurname") String studentSurname,
                         @RequestParam(value = "studentName") String studentName,
                         @RequestParam(value = "studentPatronymic") String studentPatronymic,
                         @RequestParam(value = "studentNumber") String studentNumber) {

  Student lvStudent = new Student(studentSurname, studentName, studentPatronymic, Long.valueOf(studentNumber));
  if (service.checkLogin(lvStudent)) {
    return "OK";
  } else {
    return "Проверьте введенные данные! (Также возможна проблема в серверах ДГУ)";
  }
}

@RequestMapping(value = "/student", method = RequestMethod.POST)
@ResponseBody
public ResponseEntity<?> checkLogin(Student student) {
  if (service.checkLogin(student)) {
    return ResponseEntity.ok();
  } else {
    return ResponseEntity.badRequest().body("Проверьте введенные данные! (Также возможна проблема в серверах ДГУ)");
  }
}