Mockito vs @Configurable

Question

我正在尝试为一些通常由Spring管理的代码编写JUnit测试。

假设我有这个:

@Configurable
public class A {
  @Autowired MyService service;
  public void callA() { service.doServiceThings(); }
}

我可以用Mockito和PowerMock为这个类写一个测试，像这样:

@RunWith(PowerMockRunner.class)
public class ATest {
  @Spy MyService service = new MyService();
  @Before void initMocks() { MockitoAnnotations.initMocks(this); }
  @Test void test() {
    @InjectMocks A a = new A(); // injects service into A
    a.callA();
    //assert things
  }
}

但是现在我遇到了其他类构造a的实例的情况:

public class B {
  public void doSomething() {
    A a = new A(); // service is injected by Spring
    a.callA();
  }
}

如何将服务注入到B方法中创建的A的实例中?

@RunWith(PowerMockRunner.class)
public class BTest {
  @Spy MyService service = new MyService();
  @Before void initMocks() { MockitoAnnotations.initMocks(this); }
  @Test testDoSomething() {
     B b = new B();
     // is there a way to cause service to be injected when the method calls new A()?
     b.doSomething(); 
     // assert things
  }
}

Answer 1

字段注入是不好的，但仍然有一件事，你可以做的很容易存根的A实例化(或者可能我误解了什么)。让B通过构造函数注入一个工厂。

public class B {
    private final AFactory aFactory;
    public B(AFactory aFactory) {
        this.aFactory=aFactory;
    }
    public void doSomething() {
    A a = aFactory.getA();
    a.callA();
    }
}

然后你可以创建一个Mock of aFactory，并通过构造函数把它注入到B。