使用测试类的构造函数进行依赖项注入

Question

我的FixValueConceptIntegration类有一个构造函数，它看起来像这样：

private ReferenceConceptHelper referenceConceptHelper;
private ConceptClientFacade conceptClientExternalFacade;
public FixValueConceptIntegration()
{
referenceConceptHelper = JournalSingletonFactory.getInstance().getSingletonInstance(ReferenceConceptHelper.class);
conceptClientExternalFacade = JournalSingletonFactory.getInstance().getSingletonInstance(ConceptClientFacade.class);
}

所以现在我将使用 Mockito 对其进行测试。

如果我们有一个像这样的构造函数

public FixValueConceptIntegration(ReferenceConceptHelper referenceConceptHelper, ConceptClientFacade conceptClientExternalFacade)
{
this.referenceConceptHelper = referenceConceptHelper
this.conceptClientExternalFacade = conceptClientExternalFacade
}

我知道当我们要测试类时很容易初始化。因为我们可以模拟ReferenceConceptHelper和ConceptClientFacade类。 然后我们可以像这样在@BeforeMethod使用它：

@BeforeMethod
public void beforeMethod()
{
MockitoAnnotations.initMocks(this);
fixValueConceptIntegration = new FixValueConceptIntegration(referenceConceptHelper, conceptClientExternalFacade);
}

然后所有的依赖项都将注入到构造函数中，无需担心。 所以这里的问题是我无法弄清楚如何将这些依赖项(通过模拟)注入到上述可测试类中。

Answer 1

只需对类使用mock(org.mockito.Mockito.mock) 方法，并使用when方法来模拟方法调用：

@Test
public void yourTest() {
ReferenceConceptHelper referenceConceptHelper = mock(ReferenceConceptHelper .class);
when(referenceConceptHelper.someMethod(any()).thenReturn("hello");
ConceptClientFacade conceptClientExternalFacade = mock(ConceptClientExternalFacade.class);
when(conceptClientExternalFacade.someMethod(any()).thenReturn("world");
FixValueConceptIntegration integration = new FixValueConceptIntegration(referenceConceptHelper, conceptClientExternalFacade);
assertEquals("hello world", integration.methodThatYouWouldLikeToTest());
}

在这种情况下，您无需使用@BeforeMethod或调用MockitoAnnotations.initMocks(this);。对于单元测试，仅当无法直接访问注入的类(通常在使用字段注入时)时，initMocks才有用。

但是如果你想使用注释(我个人不喜欢)，你可以做这样的事情：

@InjectMocks
private FixValueConceptIntegration integration;
@Mock
private ReferenceConceptHelper referenceConceptHelper;
@Mock
private ConceptClientFacade conceptClientFacade;
@Before
public void init() {
MockitoAnnotations.initMocks(this);
when(referenceConceptHelper.someMethod(any()).thenReturn("hello");
when(conceptClientExternalFacade.someMethod(any()).thenReturn("world");
}
@Test
public void yourTest() {
assertEquals("hello world", integration.methodThatYouWouldLikeToTest());
}

Answer 2

我用TestNGBase扩展了我的测试类，它扩展了PowerMockTestCase。 然后像这样将registerMockSingleton方法添加到TestNGBase类中;

protected <E, I extends E> void registerMockSingleton(Class<E> typeInterface, I mock)
{
delegate.registerMockSingleton(typeInterface, mock);
}

然后像这样向构造函数注入模拟依赖项;

@Override
public void performSetup() {
MockitoAnnotations.initMocks(this);
registerMockSingleton(ReferenceConceptHelper.class,mockReferenceConceptHelper);
registerMockSingleton(ConceptClientFacade.class,mockConceptClientExternalFacade);
fixValueConceptIntegration = new FixValueConceptIntegration();
}
@Override
protected void performTearDown() throws Exception
{
fixValueConceptIntegration = null;
}

都解决了!!(我的可测试类构造函数不会向构造函数注入依赖项 参数。这就是为什么我这样解决了我的问题)