Springboot测试问题：Mockito返回空对象

Question

我正在尝试构建一个使用gradle作为构建工具和openjdk-11的原型。这个原型将在springboot框架上构建一个rest-api。

我的模块与rest api调用配合良好，并返回了预期结果。然而，当我现在试图为RESTAPI编写测试时，测试失败了，因为Mockito返回了空对象。如果您能了解我应该如何为这个rest api编写测试或如何修复它，我将不胜感激。

我的控制器：

@RestController
public class GreetingController {

private static final String template = "Hello, %s!";
private final AtomicLong counter = new AtomicLong();

@Autowired
GreetingService service;

@RequestMapping("/greeting")
public Greeting greeting(@RequestParam(value="name", defaultValue="World") String name) {
    return service.getGreetings(0L, String.format(template, name));
}
}

服务：

@Service
public class GreetingService {

public Greeting getGreetings() {
    return new Greeting(1L, "Hello World");
}

public Greeting getGreetings(Long id, String name) {
    return new Greeting(id, name);
}
}

模型：

@Builder
@Data
@RequiredArgsConstructor
@JsonDeserialize(builder = Greeting.class)
public class Greeting {
    @NonNull
    private Long id;

    @NonNull
    private String content;

}

主要类别：

@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

我签署了以下文件：

gradle bootrun

然后从浏览器中尝试：

http://localhost:8080/greeting 

那回来了：

{"id":0,"content":"Hello, World!"}

再次尝试：

http://localhost:8080/greeting?name=Patty

结果是：

{"id":0,"content":"Hello, Patty!"}

现在，我正在尝试编写测试，以通过编程验证类似于上述调用的api调用。所以我试着：

@RunWith(MockitoJUnitRunner.class)
public class GreetingControllerTest {

    private MockMvc mockMvc;

    @Mock
    private GreetingService service;

    @InjectMocks
    private GreetingController controller


    @Test
    public void testGreeting() throws Exception {

        Greeting  greeting  = new Greeting(0L,"Patty!");
        String expectedResponse  = "{\"id\":0,\"content\":\"Hello, Patty!\"}";


        //JacksonTester.initFields(this, new ObjectMapper());
        mockMvc = MockMvcBuilders.standaloneSetup(controller)
                .build();
        Mockito.when(service.getGreetings(0L,"Patty")).thenReturn(greeting);


        MockHttpServletResponse response = mockMvc
                .perform(get("/greeting?name=Patty")
                        .contentType(MediaType.ALL))
                .andReturn()
                .getResponse();


        assertThat(response.getStatus()).isEqualTo(HttpStatus.OK.value());
        assertThat(response.getContentAsString()).isEqualTo(expectedResponse)


    }




}

错误msg是：

org.junit.ComparisonFailure: 
Expected :"{"id":0,"content":"Hello, Patty!"}"
Actual   :""

从此行失败：

assertThat(response.getContentAsString()).isEqualTo(expectedResponse)

提前谢谢。

Answer 1

这有助于我理解：Mockito-thenReturn总是返回null对象

我换了Mockito。当部分到：

Mockito.when(service.getGreetings(Mockito.anyLong(),Mockito.anyString())).thenReturn(greeting);

而且奏效了