单元测试如何使用Mockito模拟存储库

Question

我有一个问题与存根我的存储库。有人建议我只创建另一个application.properties（我没有这样做），并使用像H2这样的内存数据库。不过，我想知道我是否可以只是存根调用，这样当调用MyDataService.FindById(id)而不是试图从数据库中获取它时，就可以返回一个模拟对象？

public class MyServiceImplTest 
{
    private MyDataService myDataService;
    private NyService myService;
    private MyRepository myRepository;

    @Before
    public void setUp() {
        myDataService = Mockito.mock(MyDataServiceImpl.class);
        myService = new MyServiceImpl(myDataService);
    }

    @Test
    public void getById_ValidId() {
        doReturn(MyMockData.getMyObject()).when(myDataService).findById("1");
        when(myService.getById("1")).thenReturn(MyMockData.getMyObject());
        MyObject myObject = myService.getById("1");

        //Whatever asserts need to be done on the object myObject 
    }
}

@Service
public class MyServiceImpl implements MyService {
    MyDataService myDataService;

    @Autowired
    public MyServiceImpl(MyDataService myDataService) {
        this.myDataService = myDataService;
    }

    @Override
    public MyObject getById(String id) {
        if(id == null || id == "") {
            throw new InvalidRequestException("Invalid Identifier");
        }

        MyObject myObj;
        try {
            myObj = myDataService.findById(id);
        }catch(Exception ex) {
            throw new SystemException("Internal Server Error");
        }

        return myObj;
    }
}

@Repository
@Qualifier("MyRepo")
public class MyDataServiceImpl {

    @PersistenceContext
    private EntityManager em;

    private MyRepository repository;

    @Autowired
    public MyDataServiceImpl(MyRepository repository) {
        super(repository);
        this.repository = repository;
    }

    public MyObject findById(String id) {
        P persitentObject = repository.findOne(id);
        //Calls to map what persitentObject holds to MyObject and returns a MyObject 
    }
}

public interface MyRepository extends CrudRepository<MyObjectPO, String>, JpaSpecificationExecutor<MyObjectPO> {

}

Answer 1

首先，我要说的是，通过使用构造函数注入而不是字段注入（这使得用模拟编写测试要简单得多），您已经走上了正确的轨道。

public class MyServiceImplTest 
{
    private MyDataService myDataService;
    private NyService myService;

    @Mock
    private MyRepository myRepository;

    @Before
    public void setUp() {
        MockitoAnnotations.initMocks(this); // this is needed for inititalizytion of mocks, if you use @Mock 
        myDataService = new MyDataServiceImpl(myRepository);
        myService = new MyServiceImpl(myDataService);
    }

    @Test
    public void getById_ValidId() {

        doReturn(someMockData).when(myRepository).findOne("1");
        MyObject myObject = myService.getById("1");

        //Whatever asserts need to be done on the object myObject 
    }
}

调用一直从您的服务-->DataService发出。但是只有存储库调用被模拟。
这样，您可以控制和测试类的所有其他部分（包括service和dataService）和只模拟存储库调用。