Security Principal

public User getCurrentUser(Principal principal) {
    System.out.println("principal.getName() = " + principal.getName());
    System.out.println(" userService.getByLogin(principal.getName()) = " + userService.getByLogin(principal.getName()));
    return userService.getByLogin(principal.getName());
}

/**
 * Edit user method
 * !! if Change user.login you must to re singIn on client !!
 */
@RequestMapping(method = RequestMethod.POST)
@ResponseBody
public Object editUser(Principal principal, @RequestBody User user, HttpServletResponse response) {
    response.setStatus(400);
    // Check user for situation when login or email is busy
    User checker = userService.getByEmail(user.getEmail());
    if ((checker != null) && (checker.getUserId() != user.getUserId())) {
        return new Constraint("email", user.getEmail(), "Email " + user.getEmail() + " is busy");
    } else {
        checker = userService.getByLogin(user.getLogin());
        if ((checker != null) && (checker.getUserId() != user.getUserId())) {
            return new Constraint("login", user.getLogin(), "Login " + user.getLogin() + " is busy");
        }
    }
    //try to edit user
    try {
        response.setStatus(200);
        if (user.getUserId() == getCurrentUser(principal).getUserId())
            return userService.editUser(user);
        else
            throw new BadRequestException();
    } catch (ConstraintViolationException e) {
        e.printStackTrace();
        response.setStatus(400);
        return getInCorrectValues(e);
    }
}