DexMaker Mockito是存根、间谍、部分还是什么？

Question

当我用Mockito.mock()模拟一个对象时，我希望该对象有存根方法返回null、0、false等，而没有我模拟的真实对象的任何代码。我认为这是Java的默认行为，但Android似乎将真实对象作为模拟的一部分。我该如何避免这种情况？

public class MockTest extends InstrumentationTestCase {
  public void testMock() {
    Engine engine = mock(Engine.class);
    Car car = new Car(engine);

    car.start(); // Null pointer error, because Engine.starter is null.

    verify(engine, Mockito.times(1)).engageStarter();
  }


  public static class Car {
    private final Engine engine;

    public Car(Engine engine) {
      this.engine = engine;
    }

    public void start() {
      engine.engageStarter();
    }
  }


  public static class Engine {
    private final Starter starter;

    public Engine(Starter starter) {
      this.starter = starter;
    }

    void engageStarter() {
      starter.spin();
    }
  }


  public static class Starter {
    public void spin() {
      System.out.println("Start or explode");
    }
  }
}

Answer 1

解决方案是使engageStarter()成为公共的。