Question

I want to test a JSF Backing-Bean method “isInProgress” that delegates to a service method “isInProgress”. When the service method throws an exception, the bean should put an event on a specific event logger and return false.

When I debug the following test, I get into the catch-block. The mocked service does not throw the exception, but returns a “default answer” which is false for th boolean. What am I doing wrong?

I also wonder if the try-catch around the “when” call can be avoided somehow, as the actual exception is swallowed by the bean under test. In fact I think “declaratively” passing the name of the method to the “when” should suffice. Is there a way to get that cleaner ?

@Test
public void testIsInProgressExeption() {
    //prepare object and inputs
    MyBean bean = new MyBean();
    MyService service = mock(MyAdapterService.class);
    bean.setService(service);

    try {
        when(bean.getService().isInProgress()).thenThrow(new Exception());
    } catch (Exception e) {

        //prepare expected object and result
        MyBean expectedBean = new MyBean();
        expectedBean.setService(service);
        boolean expected = false;

        //execute method under test
        boolean actual = bean.isInProgress();

        //check return values and exceptions
        assertEquals(expected, actual);

        //check that bean did not change unexpectedly
        assertTrue(bean.equals(expectedBean));

        //check sideeffects on event log
        assertTrue(logEvents.containsMessage("MDI09"));
    }

}

For reference here is the updated Test:

@Test
public void testIsInProgressExeption() throws Exception {
    //prepare object and inputs
    MyBean bean = new MyBean();
    MyService service = mock(MyAdapterService.class);
    bean.setService(service);

    when(bean.getService().isInProgress()).thenThrow(new Exception());

    //prepare expected object and result
    MyBean expectedBean = new MyBean();
    expectedBean.setService(service);
    boolean expected = false;

    //execute method under test
    boolean actual = bean.isInProgress();

    //check return values and exceptions
    assertEquals(expected, actual);

    //check that bean did not change unexpectedly
    assertTrue(bean.equals(expectedBean));

    //check sideeffects on event log
    assertTrue(logEvents.containsMessage("MDI09"));

}

Answer 1

Move the when clause out of the try block and change it to:

when(service.isInProgress()).thenThrow(new Exception());

Now it should throw an exception when called.