how can I mock a service to throw an exception a method that returns a List?

Question

I am facing this little issue. I have a service this way

public class Myservice {

   MyRestService myRestService; 

    public List<String> getNames() throws RestClientException {
        return myRestService.getNames();
    }

....

and a controller that is like this:

@RequestMapping(value = URL, method = GET)
    public ModelAndView display(final ModelMap model) {
        ....
        try{
            List<String> listOfNames = myService.getNames();
        }catch(RestClientException e){
            LOG.error("Error when invoking Names service", e);
        }
        model.addAttribute("names", listOfNames);
        return new ModelAndView(VIEW, model);
    }....

So far works so good, the unit testing for the case the service actually returns a list of Strings works fine.

But since the service calls another one that is basically a rest client that could throw an exception, I want to mock that case.

If I have myService calling myRestClientService where myRestClientService throws an exception should I hadd to the method signature "throws Exception" ?

 final RestClientException myException =  mockery.mock(RestClientException.class);
        mockery.checking(new Expectations() {
            {
                oneOf(myService).getNames();
                will(returnValue(myException));
...

But I get an error that I cannot throw an exception from a method that only return List is there anyway to fix this? How could I test it?

Answer 1

According to the documentation Throwing Exceptions from Mocked Methods you should use throwException rather than returnValue. It means code should be something like

 will(throwException(myException));