@Test
    public void exceptionThrownIfSubmittedOnIsNullWithinFormData() {

        when(budgetFormData.getSubmittedOn()).thenReturn(null);

        try {
            budget.buildBudget(budgetFormData);
            fail("SubmittedOn is null.");
        } catch (Exception e) {
            System.out.println("SubmittedOn is null");
        }

    }