Java 使用Mockito进行单元测试时使用空指针

我正在为我的应用程序创建一个spring引导API。我试图使用mockito对我的服务实现进行单元测试，以模拟细节。该服务将向数据库中添加新的建筑实体。下面是服务实现和测试实现。 屋宇装备：

@Slf4j
@Service
public class BuildingServiceImpl implements BuildingService {

private BuildingRepository buildingRepository;
private BuildingRequestToEntityMapper buildingRequestToEntityMapper;

public BuildingServiceImpl(BuildingRepository buildingRepository, BuildingRequestToEntityMapper 
buildingRequestToEntityMapper){
this.buildingRepository=buildingRepository;
this.buildingRequestToEntityMapper=buildingRequestToEntityMapper;
}

public HttpStatus addBuilding(BuildingRequest buildingRequest){
    log.info("Inside addBuilding() service");
    BuildingEntity buildingEntity = buildingRequestToEntityMapper.map(buildingRequest);
    buildingRepository.save(buildingEntity);
    log.info("Building saved "+ buildingEntity);
    return HttpStatus.CREATED;
}

BuildingServiceImpl\u UT

@RunWith(MockitoJUnitRunner.class)
public class BuildingServiceImpl_UT {

@Mock
BuildingRequestToEntityMapper buildingRequestToEntityMapper;

@Mock
BuildingRepository buildingRepository;

@InjectMocks
BuildingServiceImpl buildingServiceImpl;

@Test
public void buildingService_MapsRequest_AndSaveEntity(){
BuildingRequest buildingRequest = BuildingRequest.builder()
            .name("TestName")
            .telephone("4444444444")
            .postcode("TEst")
            .address("testAddress").build();

   when(buildingServiceImpl.addBuilding(any(BuildingRequest.class))).thenReturn(HttpStatus.CREATED);
    when(buildingRepository.save(any(BuildingEntity.class))).thenReturn(new BuildingEntity());

    buildingServiceImpl.addBuilding(buildingRequest);
    verify(buildingRepository, times(1)).save(any());
}

我模拟了映射器和存储库并将它们注入到服务中，但是当我运行测试时，在测试类中的第一个when（）.thenReturn（）语句中会出现空指针异常。请帮忙。谢谢

这：

when(buildingServiceImpl.addBuilding(any(BuildingRequest.class))).thenReturn(HttpStatus.CREATED);

---

没有必要，您要测试方法：

addBuilding

不要模拟它。

我不明白您的第一个when（）。然后返回（）！您尝试在buildingServiceImpl上执行此操作，这不是一个模拟！更进一步，这是没有意义的，因为你想测试这个方法！ 我认为应该为模拟buildingRequestToEntityMapper定义when（）.thenReturn（），但在实现中，不需要为buildingRequestToEntityMapper.map（）定义返回。在这种情况下，变量buildingEntity的值为null，该值应在测试用例中起作用

@RunWith(MockitoJUnitRunner.class)
public class BuildingServiceImpl_UT {

@Mock
BuildingRequestToEntityMapper buildingRequestToEntityMapper;

@Mock
BuildingRepository buildingRepository;

@InjectMocks
BuildingServiceImpl buildingServiceImpl;

    @Test
    public void buildingService_MapsRequest_AndSaveEntity(){
    BuildingRequest buildingRequest = BuildingRequest.builder()
                .name("TestName")
                .telephone("4444444444")
                .postcode("TEst")
                .address("testAddress").build();


        when(buildingRepository.save(any(BuildingEntity.class))).thenReturn(new BuildingEntity());

        buildingServiceImpl.addBuilding(buildingRequest);
        verify(buildingRepository, times(1)).save(any());
        verify(buildingRequestToEntityMapper).map(any());
    }

当（buildingservicecimpl.addBuilding（any（BuildingRequest.class）））时删除

，然后返回（HttpStatus.CREATED）测试中的行。