java使用mockito填充列表

Question

我有一门课要考

public class MinicabManager {
public static Set<Driver> allDrivers ;
public static Set<Passenger> allPassengers;
public static List<Trip> trips;

public static Set<Driver> findFakeDrivers() {
    Set<Driver> fakeDrivers = new HashSet();
    for (Trip t : trips) {
        for (Driver d : allDrivers) {
            if (t.getDriver().getDriver() != d.getDriver()) {
                fakeDrivers.add(d);
            }
        }
    }
    return fakeDrivers;
}

运行此测试时，我会收到NullPointerException：

@RunWith(MockitoJUnitRunner.class)
public class MinicabManagerTest {
@Mock
Set<Driver> allDrivers;
@Mock
Set<Passenger> allPassengers;
@Mock
List<Trip> trips;
@InjectMocks
MinicabManager minicabManager;
@Before
public void setUp() {
    MockitoAnnotations.initMocks(this);
minicabManager = new MinicabManager();

    allDrivers = new HashSet();
    allPassengers = new HashSet();
    trips = new ArrayList();

    Driver d1 = new Driver();
    d1.setDriver("d1");
    Driver d2 = new Driver();
    d2.setDriver("d2");
    allDrivers.add(d1);
    allDrivers.add(d2);

    Passenger p1 = new Passenger();
    p1.setName("p1");
    Passenger p2 = new Passenger();
    p2.setName("p2");
    allPassengers.add(p1);
    allPassengers.add(p2);

    Trip t1 = new Trip();
    t1.setDriver(d1);
    t1.setPassengers(allPassengers);
    trips.add(t1);
}
@Test
public void testFindFakeDrivers() throws Exception {
    Set<Driver> result = minicabManager.findFakeDrivers();
}

如何填充列表？ 据我所知，InjectMock由模拟列表和集合注入，然后在每个测试用例之前填充。但我得到了NullPointerException

Answer 1

• 不要模仿对象和正常地实例化它们。要么做一个，要么做另一个。@Mock注释将为您创建一个模拟对象，您可以随时在测试中使用它
• 要知道，模拟对象是一个“假”对象，它只假装是某一类型的对象。因此，如果在模拟对象上调用任何方法/字段，它实际上什么都不会做（对于非void方法，它总是返回null）
• 您不需要指定MockitoJUnitRunner和调用initMocks()方法。一个就够了
• 正如其他人所提到的，您的测试似乎不需要模拟。所以它可能看起来像这样：

public class MinicabManagerTest {

        @Before
        void setUp() {

            Set<Driver> allDrivers = new HashSet<>();
            Set<Passenger> allPassengers = new HashSet<>();
            List<Trip> trips = new ArrayList<>();

            Driver d1 = new Driver();
            d1.setDriver("d1");
            Driver d2 = new Driver();
            d2.setDriver("d2");
            allDrivers.add(d1);
            allDrivers.add(d2);

            Passenger p1 = new Passenger();
            p1.setName("p1");
            Passenger p2 = new Passenger();
            p2.setName("p2");
            allPassengers.add(p1);
            allPassengers.add(p2);

            Trip t1 = new Trip();
            t1.setDriver(d1);
            t1.setPassengers(allPassengers);
            trips.add(t1);

            MinicabManager.allDrivers = allDrivers;
            MinicabManager.allPassengers = allPassengers;
            MinicabManager.trips = trips;
        }

        @Test
        public void testFindFakeDrivers() throws Exception {
            Set<Driver> result = MinicabManager.findFakeDrivers();
            // assertions about the result here
        }

另外，注意不要将字符串与=和!=进行比较。使用equals()方法