Question

更喜欢使用模拟和单元测试助手进行弹簧测试：

模拟服务替换了多个依赖项

@Controller
@RequestMapping("/people")
public class PeopleController {
    @Autowired
    protected PersonService personService;
    @GetMapping
    public ModelAndView people(Model model) {
        for (Person person: personService.getAllPeople()) {
            model.addAttribute(person.getName(), person.getAge());
        }
        return new ModelAndView("people.jsp", model.asMap());
    }
}

私人MockMvc模拟Mvc：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
public class PeopleControllerTest {
    @Autowired
    PersonService personService;

    private MockMvc mockMvc;

    @Configuration
    static class Config {
        // Other beans
        @Bean
        public PersonService getPersonService() {
            return mock(PersonService.class);
        }
    }
    @Test
    public void testPeople() throws Exception {
        // When
        ResultActions actions = mockMvc.perform(get("/people"));
    }
}

我想运行mockMvc

时出错

java.lang.NullPointerException

Answer 1

从源代码中，我看到mockMvc没有任何值，这就是为什么它在此代码行中命中“ java.lang.NullPointerException”：

ResultActions actions = mockMvc.perform(get("/people"));

要使其运行，我认为首先需要赋予嘲笑价值。
通过构造函数：

@Test
public void testPeople() throws Exception {
    mockMvc = new MockMvc();
    // When
    ResultActions actions = mockMvc.perform(get("/people"));
}

或自动接线：

@Autowired
MockMvc mockMvc

取决于MockMvc类的目的

Answer 2

这是因为您从未在代码中初始化mockMvc，而访问它的时间点将导致nullPointerException。您需要在使用它之前对其进行初始化，并且由于类中的多个测试可能正在使用它，所以最好的方法是使用setup()注释的@before方法。请尝试以下：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
public class PeopleControllerTest {
@Autowired
PersonService personService;

@Autowired
private WebApplicationContext wac;

private MockMvc mockMvc;

@Before
public void setup() {
  mockMvc = MockMvcBuilders.webAppContextSetup(wac).build();


@Configuration
static class Config {
    // Other beans
    @Bean
    public PersonService getPersonService() {
        return mock(PersonService.class);
    }
}
@Test
public void testPeople() throws Exception {
    // When
    ResultActions actions = mockMvc.perform(get("/people"));
}
}

Answer 3

执行以下步骤：

创建服务模拟而不是原始服务（“ PersonServiceMock”）

通过服务模拟替换原始服务

    @Autowired
    PersonService personService;

    @Autowired
    PeopleController peopleController;

    private MockMvc mockMvc;

    @Before
    public void setup() {
    peopleController = new PeopleController(new personServiceMock());
    mvc = MockMvcBuilders.standaloneSetup(peopleController).build();
   }    

    @Configuration
    static class Config {
        // Other beans
        @Bean
        public PersonService getPersonService() {
            return mock(PersonService.class);
        }
    }
    @Test
    public void testPeople() throws Exception {
        // When
        ResultActions actions = mockMvc.perform(get("/people"));
    }
}

通过模拟服务进行弹簧控制器测试

3 个答案: