如何使用Mockito在Spring Boot中模拟异步(@Async)方法?

使用mockito模拟异步(@Async)方法的最佳方法是什么?提供以下服务:

@Service
@Transactional(readOnly=true)
public class TaskService {
    @Async
    @Transactional(readOnly = false)
    public void createTask(TaskResource taskResource, UUID linkId) {
        // do some heavy task
    }
}

Mockito的验证如下:

@RunWith(SpringRunner.class)
@WebMvcTest(SomeController.class)
public class SomeControllerTest {
    @Autowired
    MockMvc mockMvc;
    @MockBean    
    private TaskService taskService;
    @Rule
    public MockitoRule mockitoRule = MockitoJUnit.rule();

    // other details omitted...

    @Test
    public void shouldVerify() {
        // use mockmvc to fire to some controller which in turn call taskService.createTask
        // .... details omitted
        verify(taskService, times(1)) // taskService is mocked object
            .createTask(any(TaskResource.class), any(UUID.class));
    } 
}

上面的测试方法应该总是抛出:

org.mockito.exceptions.misusing.InvalidUseOfMatchersException: 
Misplaced argument matcher detected here:

-> at SomeTest.java:77) // details omitted
-> at SomeTest.java:77) // details omitted 

You cannot use argument matchers outside of verification or stubbing.
Examples of correct usage of argument matchers:
    when(mock.get(anyInt())).thenReturn(null);
    doThrow(new RuntimeException()).when(mock).someVoidMethod(anyObject());
    verify(mock).someMethod(contains("foo"))

Also, this error might show up because you use argument matchers with methods that cannot be mocked.
Following methods *cannot* be stubbed/verified: final/private/equals()/hashCode().
Mocking methods declared on non-public parent classes is not supported.

如果我从TaskService.createTask方法中删除@Async,则不会发生上述异常.

Spring Boot版本:1.4.0.RELEASE

Mockito版本:1.10.19

最佳答案
我们希望在1.4.1中修复bug in Spring Boot.问题是你的模拟TaskService仍然被异步调用,这打破了Mockito.

您可以通过为TaskService创建一个接口并创建一个模拟来解决此问题.只要你只在实现上留下@Async注释就可以了.

像这样的东西:

public interface TaskService {

    void createTask(TaskResource taskResource, UUID linkId);

}

@Service
@Transactional(readOnly=true)
public class AsyncTaskService implements TaskService {

    @Async
    @Transactional(readOnly = false)
    @Override
    public void createTask(TaskResource taskResource, UUID linkId) {
        // do some heavy task
    }

}

转载注明原文:如何使用Mockito在Spring Boot中模拟异步(@Async)方法? - 代码日志