java - 在 JUnit/Mockito 测试中使用 Mocked 对象

Question

我有一个 JUnit 测试，内容为

public class  EventHandlerTest  {

    @Mock
    ThreadPoolExtendedExecutor threadPoolExtendedExecutor;

    private EventHandler handler;
    private Map<Queue<SenderTask>> subBuffers = new HashMap<>();


    @Before
    public void setUp() {
        // PROBLEM: threadPoolExtendedExecutor null!
        handler = new EventHandler(subBuffers, threadPoolExtendedExecutor);
    }


}

当我在setUp中调用new时，我有threadPoolExtendedExecutor=null。我想插入一些模拟的threadPoolExtendedExecutor，这样，我在调用它的方法时就不会遇到NullPointer问题(所以简单的接口(interface)模拟对我来说现在就足够了)

Answer 1

您可以简单地使用(在setUp中)来模拟它

threadPoolExtendedExecutor = mock(ThreadPoolExtendedExecutor.class);

@Before
public void setUp() {
    threadPoolExtendedExecutor = mock(ThreadPoolExtendedExecutor.class);
    handler = new EventHandler(subBuffers, threadPoolExtendedExecutor);
}

您也可以让 MockitoJUnitRunner 为您做这件事:不要忘记通过使用 @InjectMocks 注释来在测试的服务中注入(inject)模拟

@RunWith(MockitoJUnitRunner.class)
public class  EventHandlerTest  {

    @Mock
    ThreadPoolExtendedExecutor threadPoolExtendedExecutor;