Bear Test

@Slf4j
public class UserHandlerExceptionResolver implements HandlerExceptionResolver {

    private final ObjectMapper objectMapper = new ObjectMapper();

    @Override
    public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {

        try {

            if (ex instanceof UserException) {
                log.info("UserException resolver to 400");
                String acceptHeader = request.getHeader("accept");
                response.setStatus(HttpServletResponse.SC_BAD_REQUEST);

                if ("application/json".equals(acceptHeader)) {
                    Map<String, Object> errorResult = new HashMap<>();
                    errorResult.put("ex", ex.getClass());
                    errorResult.put("message", ex.getMessage());
                    String result = objectMapper.writeValueAsString(errorResult);

                    response.setContentType("application/json");
                    response.setCharacterEncoding("utf-8");
                    response.getWriter().write(result);
                    return new ModelAndView();
                } else {
                    // TEXT/HTML
                    return new ModelAndView("error/500");
                }
            }

        } catch (IOException e) {
            log.error("resolver ex", e);
        }

        return null;
    }
}