java - PowerMockito thenReturn 返回错误的对象

Question

我在测试中使用 PowerMockito 模拟静态缓存。一般来说，缓存的工作原理是这样的:

Cache.getInstance().findEntityById(AbstractDTO);
// so, if I want a TypeA, I use:
TypeADTo typeADTO = // go the dto from the db ...
TypeA = Cache.getInstance().findEntityById(typeADTO);

静态缓存在应用程序中被广泛使用。因此，为了在单元测试中使用它，我使用:

    PowerMockito.mockStatic( Cache.class );
    final Cache mockedCache = PowerMockito.mock( Cache.class );
    PowerMockito.when( Cache.getInstance() ).thenReturn( mockedCache );
// mock all I want to get
  TypeA typeA = new TypeA(some parameters);
  TypeB typeB = new TypeB(some parameters);

PowerMockito.when(
        Cache.getInstance().findEntityByBusinessId(
                Mockito.any( TypeADTO.class ) ) ).thenReturn( typeA );
PowerMockito.when(
        Cache.getInstance().findEntityByBusinessId(
                Mockito.any( TypeADTO.class ), Mockito.anyBoolean() ) )
        .thenReturn( typeA );


PowerMockito.when(
        Cache.getInstance().findEntityByBusinessId(
                Mockito.any( TypeBDTO.class ) ) ).thenReturn(
        tybeB );
PowerMockito.when(
        Cache.getInstance().findEntityByBusinessId(
                Mockito.any( TypeBDTO.class ), Mockito.anyBoolean() ) )
        .thenReturn( typeB );

我为所有需要的类型创建了一些模拟语句。 (正如您所看到的，有不止一种方法需要针对一种类型进行模拟)

问题是:power mockito 总是返回在最后一个 PowerMockito.when(...) 语句中设置的对象。

Answer 1

您尝试过链接调用吗？此外，您还可以使用 Mockito 的 when 单词。

Mockito.when(Cache.getInstance().findEntityByBusinessId(any(TypeBDTO.class),anyBoolean()))
       .thenReturn( typeA )
       .thenReturn( typeB );

这将按照该顺序准确记录模拟。

供将来引用的完整示例:

@RunWith(PowerMockRunner.class)
@PrepareForTest({BusinessUtility.class})
public class BusinessUtilityTest {

    @Before
    public void setUp() {
        PowerMockito.mockStatic(BusinessUtility.class);
    }

    @Test
    public void testStatic() {
        when(BusinessUtility.getDate())
                         .thenReturn(new Date(1111))
                         .thenReturn(new Date(2222));

        assertThat(BusinessUtility.getDate()).hasTime(1111);
        assertThat(BusinessUtility.getDate()).hasTime(2222);
    }
}

提示:

• 使用静态导入使代码更具可读性
• 使用 PowerMockito 只是为了初始化您的静态类，然后继续使用 Mockito
• 尽可能避免静态类，测试会更困难，如您所见；)

编辑 ----------------------------------------------------------

看一下这个示例，它与您当前的用例类似:

类(class):

static class BusinessUtility {
    public static <T> T getObject(T instance) {
        return null;
    }

    public static <T> T getObject(T instance, Boolean b) {
        return null;
    }
}

测试:

@Test
public void testStatic() {
    //arrange
    when(BusinessUtility.getObject(anyString()))
            .thenReturn("one")
            .thenReturn("two");

    when(BusinessUtility.getObject(any(Date.class), anyBoolean()))
            .thenReturn(new Date(1111))
            .thenReturn(new Date(2222));

    //act
    String firstStr = BusinessUtility.getObject("asdf");
    String secondStr = BusinessUtility.getObject("qwerty");

    Date firstDate = BusinessUtility.getObject(new Date(), true);
    Date secondDate = BusinessUtility.getObject(new Date(), false);

    //assert
    assertThat(firstStr).isEqualTo("one");
    assertThat(secondStr).isEqualTo("two");

    assertThat(firstDate).isEqualTo(new Date(1111));
    assertThat(secondDate).isEqualTo(new Date(2222));
}