Slice Test (Not Integration Test)

• Partial Spring context
  • Not real and whole context
• Only one layer
  • Like service layer, repo layer, …
• Other layers mocked

@WebMvcTest

Flow

HTTP Request
↓
Controller (REAL)
↓
Service (@MockBean)
❌ Repo
❌ DB

So must use @MockBean, else Spring will say bean not found.

Example:

@WebMvcTest(UserController.class)
class UserControllerTest {

    @Autowired
    MockMvc mockMvc;

    @MockBean
    UserService userService;
}

@DataJpaTest

• Test repository + DB behavior, load
  • JPA entities
  • Repositories
  • In-memory DB

@DataJpaTest
class UserRepositoryTest {

    @Autowired
    UserRepository repo;
}