@Test
public void show_How_Stubbing_Works() {
/**
* Set up phase.
*
* <p>1. Create Mocks, 2. Stub only required methods 3. Inject the mock objects.
*/
// Stubbing
when(mockedBookDao.getTop5BooksOnSale()).thenReturn(top5BooksOnSaleList);
when(mockedBookDao.getSpecialPromotionsBasedOnUser(Matchers.<User>anyObject()))
.thenReturn(booksOnSpecialPromotionList);
// Injecting mocked DAO
promotionsService.setBookDao(mockedBookDao);
// Calling business method
final List<Book> promotionList = promotionsService.getSimplePromotions(user);
// Verification of behavior
verify(mockedBookDao).getSpecialPromotionsBasedOnUser(user);
verify(mockedBookDao, never()).getTop5BooksOnSale();
assertNotNull(promotionList);
assertTrue(
promotionList.size()
== 3); // Stubbed method being called because the size is 3. The real method returns 1
// element list.
}
/**
* Test to show if we do not stub methods in a mocked object, we will get the defaults:
*
* <p>From mockito website:
*
* <p>By default for all methods that return value, mock returns null, an empty collection or
* appropriate primitive/primitive wrapper value (e.g: 0, false, ... for int/Integer,
* boolean/Boolean, ...).
*/
@Test
public void simple_Non_Stubbed_Mocks_Will_Cause_Default_Values_To_Be_Returned() {
// Inject the mocked DAO
promotionsService.setBookDao(mockedBookDao);
// Business logic under test - Test passing of null user.
final List<Book> promotionList = promotionsService.getSimplePromotions(null);
// Regular JUnit Asserts
assertNotNull(promotionList);
assertTrue(promotionList.size() == 0); // <= NOTE: The size of the list is 0 and NOT 1.
}
@Test
public void show_Verification() {
// Inject the mocked DAO
promotionsService.setBookDao(mockedBookDao);
// Business logic under test - Test passing of null user.
final List<Book> promotionList = promotionsService.getSimplePromotions(null);
// Notice the different types of verify below
verify(mockedBookDao).getTop5BooksOnSale();
verify(mockedBookDao, times(1)).getTop5BooksOnSale();
verify(mockedBookDao, never()).getSpecialPromotionsBasedOnUser(null);
verify(mockedBookDao, atLeastOnce()).getTop5BooksOnSale();
verify(mockedBookDao, atLeast(1)).getTop5BooksOnSale();
verify(mockedBookDao, atMost(1)).getTop5BooksOnSale();
}