嗨，我的单元测试控制器返回nullpointerexception。我把我的问题归结为注解或导入。我有这套图提拉做我的测试https://spring.io/guides/gs/testing-web/. 感谢您的帮助：）

@ExtendWith(SpringExtension.class)
@WebMvcTest(OfferCompanyController.class)
public class OfferCompanyControllerUnitTest {

    @Autowired
    private MockMvc mockMvc;

    @Autowired
    private ObjectMapper objectMapper;

    @MockBean
     private OfferCompanyService offerCompanyService;

    @Test
  public  void getAllOfferCompanyTest() throws Exception {

        List<OfferCompany> offerList = new ArrayList<>();
        Date date = new Date();
        offerList.add(new OfferCompany(1L, "wesharjob","premier post", "lorem ipsum", "la ville que tu veux", date, "user", "wesharejob.co", false));
        offerList.add(new OfferCompany(2L, "wesharjob","premier post", "lorem ipsum", "la ville que tu veux", date, "user", "wesharejob.co", false));
        given(offerCompanyService.getAllOfferCompany()).willReturn(offerList);

        when(offerCompanyService.getAllOfferCompany()).thenReturn(offerList);
        mockMvc.perform(get("/api/offerCompany/listOfferCompanies")
                .contentType(MediaType.APPLICATION_JSON)
        ).andExpect(status().isOk()).andExpect(jsonPath("$", Matchers.hasSize(2)));

    }

}

offerapplicationtests（我使用import“junit.test”）

import org.junit.Test;
import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest
class OfferApplicationTests {

    @Test
    void contextLoads() {
    }

}