Spring異常の処理

 @PostMapping("/sign-in")
  public ResponseEntity<Object> login(@Valid @RequestBody LoginRequest loginRequest, BindingResult bindingResult) {
      if (bindingResult.hasErrors()) {
      	throw new CustomException("message");
      }
  }

@RestControllerAdvice
public class CustomExceptionAdvice {

    @ExceptionHandler
    public ResponseEntity<CustomErrorResponse> customExceptionHandler(CustomException e) {
        return ResponseEntity.status(HttpStatus.SOMETHING).body(customResponseBody);
    }
}

@Component
public class CustomAuthenticationEntryPoint implements AuthenticationEntryPoint {

  @Override
  public void commence(HttpServletRequest request, HttpServletResponse response, AuthenticationException authException) throws IOException {
      response.setStatus(HttpServletResponse.SC_UNAUTHORIZED); // status code 지정

      response.setContentType("application/json;charset=utf-8"); // 반환 타입 지정 

      JSONObject jsonObject = new JSONObject();
      String msg = "로그인이 필요합니다";
      jsonObject.put("message", msg);

      PrintWriter out = response.getWriter();
      out.print(jsonObject);
  }
}

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

  @Override
  protected void configure(HttpSecurity http) throws Exception {
      http.anyRequest().authenticated()
          .and().exceptionHandling()
          .authenticationEntryPoint(new CustomAuthenticationEntryPoint());
  }

@Component
public class CustomAccessDeniedHandler implements AccessDeniedHandler {
  @Override
  public void handle(HttpServletRequest request, HttpServletResponse response, AccessDeniedException accessDeniedException) throws IOException {
      ExceptionCode exceptionCode;
      exceptionCode = ExceptionCode.PERMISSION_DENIED;
      setResponse(response, exceptionCode);

  }

  private void setResponse(HttpServletResponse response, ExceptionCode exceptionCode) throws IOException {
      response.setContentType("application/json;charset=UTF-8");
      response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);

      JSONObject responseJson = new JSONObject();
      responseJson.put("message", exceptionCode.getMessage());
      responseJson.put("code", exceptionCode.getCode());

      response.getWriter().print(responseJson);
  }
}

.accessDeniedHandler(new CustomAccessDeniedHandler())