Object cannot be cast to javax.servlet.http.HttpServletRequest with Spring WebFlow

Question

I'm trying to integrate Spring MVC with Spring WebFlow. In order to share session data between both of them I came up with this solution that actually works fine:

public String prepareForPayment(RequestContext context, Authentication currentUser) {
    PaymentDetails paymentDetails = new PaymentDetails();

    // CODE HERE

    HttpServletRequest request =       (HttpServletRequest)context.getExternalContext().getNativeRequest();
    request.getSession().setAttribute("paymentDetails", paymentDetails);

    // CODE HERE

}

Then in a Controller outside webflow I can easily get session data:

PaymentDetails paymentDetails = (PaymentDetails)session.getAttribute("paymentDetails");

So above code works fine and I'm able to set and get session attributes.

Now, when I write a test for this class I get:

java.lang.ClassCastException: java.lang.Object cannot be cast to javax.servlet.http.HttpServletRequest

Why my test is throwing ClassCastException and how to solve it?

Answer 1

I checked my code again and I think the whole "problem" came from me trying to return Object instead of HttpServletRequest directly. Therefore, I caused ClassCastException. This piece of code works fine:

@RunWith(MockitoJUnitRunner.class)
public class Test {
    @Mock
    private RequestContext           context;

    @Mock
    private ExternalContext          externalContext;

    @Mock
    private HttpServletRequest       httpServletRequest;

    @Mock
    private HttpSession              httpSession;

    @Before
    public void setup() {
        Mockito.when(context.getExternalContext()).thenReturn(externalContext);
        Mockito.when(externalContext.getNativeRequest()).thenReturn(httpServletRequest);
        Mockito.when(httpServletRequest.getSession()).thenReturn(httpSession);
    }
}

Answer 2

You can get HttpServletRequest from RequestContext by calling getRequest() method.

Refer this Spring RequestContext Documentation

Answer 3

I rewritten some of the code and in the end I used:

PaymentDetails paymentDetails = (PaymentDetails) context.getConversationScope().get("paymentDetails");

and in my test:

@Mock
private RequestContext context;

@Mock
private MutableAttributeMap attMap;

private PaymentDetails paymentDetails = new PaymentDetails();

// CODE HERE

@Before
public void setUp() throws Exception {
    // Use paymentDetails methods and set values. For example:
    paymentDetails.setCurrency("GBP");

    // CODE HERE

    Mockito.when(context.getConversationScope()).thenReturn(attMap);
    Mockito.when(attMap.get("paymentDetails")).thenReturn(paymentDetails);
    // CODE HERE
}