Write JUnit test for local @ExceptionHandler

Question

I have the following controller:

class Controller {

    @ResponseStatus(HttpStatus.OK)
    @RequestMapping(value = "/verifyCert", method = RequestMethod.GET)
    public void verifyCertificate() throws CertificateExpiredException, CertificateNotYetValidException {
        certificate.checkValidity();
    }

    @ResponseStatus(HttpStatus.FORBIDDEN)
    @ExceptionHandler({CertificateExpiredException.class, CertificateNotYetValidException.class})
    public void handleCertificateValidityException(Exception e) {}
}

My goal is to that controller redirects to exception handler if certificate is not valid.

Solution

When using standaloneSetup all you are doing is performing the setup for the specific controller.

If you don't want to configure the whole application context (which you would do with webAppContextSetup instead of standaloneSetup), you can manually setup the exception handler by changing your code to:

 @Before
 public void setup() throws IOException {
     MockitoAnnotations.initMocks(this);
     mockMvc = MockMvcBuilders.standaloneSetup(controller).setHandlerExceptionResolvers(new ExceptionHandlerExceptionResolver()).build();
 }

 @Test
 public void test() throws Exception {
     mockMvc.perform(get("/verifyCert.controller").contentType(MediaType.APPLICATION_JSON).accept(MediaType.APPLICATION_JSON)).andExpect(status().isForbidden());
 }

This works because ExceptionHandlerExceptionResolver is the class that Spring MVC uses to handle exceptions based on the @ExceptionHandler annotation

Check out one of my older relevant answers that covers an ever more difficult case (the use of @ControllerAdvice on a class that contains @ExceptionHandler).