Mockito注入不适用于构造函数和setter模拟在一起

Question

我有一个类通过构造函数注入成员,其他通过setter注入.我似乎无法让Mockito注入二传手.注入的构造函数被模拟得很好,但是setter的返回为null.当我将setter-ed成员翻转到构造函数注入时,一切都很顺利.这是原始的生产代码:

@Autowired
private BetRepository betRepository;

public void setBetRepository(BetRepository betRepository) {
this.betRepository = betRepository;
}


public TournamentScoringCache(TournamentScoringCacheInitializer cacheInitializer,
        ScoringEngineInitializer scoringEngineInitializer) {
    tournamentUserStates = cacheInitializer.initCache();
    scoringEngines = scoringEngineInitializer.initEngines();
}

public <T extends SideScore> void updateGameScore(Long tournamentId, Long gameId, MatchScore<T> score) {
    Map<Long, UserTournamentState> userStates = tournamentUserStates.get(tournamentId);
    ScoringEngine<?> scoringEngine = scoringEngines.get(tournamentId);
    List<Bet> bets = betRepository.getBetsByGameId(gameId);  //HERE IS WHERE I GET THE NPE
....
}

测试代码:

@Mock
BetRepository betRepository;
@Mock
TournamentScoringCacheInitializer cacheInitializer;
@Mock
ScoringEngineInitializer engineInitializer;

@InjectMocks
private TournamentScoringCacheAndDB tournamentScoringCache;

@Test
public void testUpdateGameScore() {
....        
when(cacheInitializer.initCache()).thenReturn(utss);
    when(betRepository.getBetsByGameId(1L)).thenReturn(createBets());
    when(engineInitializer.initEngines()).thenReturn(createEngines());
    when(engine.getBetScore(bet1, score)).thenReturn(betScore);
    when(engine.getBetScore(bet2, score)).thenReturn(betScore2);

    tournamentScoringCache.updateGameScore(tournamentId, gameId, score);
....
}

有任何想法吗？

谢谢!

Answer 1

是的,@ InjectMocks注释使得Mockito EITHER进行构造函数注入,或者setter/field注入,但是从不这两个.选择的规则非常复杂,这也是我尽量避免使用@InjectMocks的原因之一.

总而言之,Mockito FIRST从类中的那些中选择一个构造函数,然后分析该构造函数是否可用于构造函数注入.它选择的那个将永远是具有最多参数的那个.如果有多个构造函数具有相同数量的参数,则未定义哪个将被选择.

如果CHOSEN构造函数的一个或多个参数的类型是基本类型,或最终类或私有类,则不会使用构造函数注入.即使有其他构造函数可以使用.

如果未使用构造函数注入,或者唯一的构造函数是默认构造函数,则将使用setter/field injection.但是setter/field注入永远不会与构造函数注入一起使用.

Answer 2

尽管强烈建议使用构造函数注入，并且强烈建议不要使用混合注入方法，但我遇到了无法重构的此类。要解决该问题，请调用initMocksexplicitly。例如：

@InjectMocks
private ThingWithMixedDependencies thing;

@Mock
private FieldInjected secondDependency;

@BeforeEach
void setUp() {
  // This cannot be a mocked field or else it will reinitialise thing.
  ConstructorInjected firstDependency = Mockito.mock(ConstructorInjected.class);
  thing = new ThingWithMixedDependencies(firstDependency);
  MockitoAnnotations.initMocks(this);
}

@Test
void checkDependencies() {
  assertThat(thing.getFirstDependency(), is(notNullValue()));
  assertThat(thing.getSecondDependency(), is(notNullValue()));
}