是否有可能在Spring ConversionService mock上调用实际方法？

Question

与标题一样，是否可以在ConversionSevice mock上调用实际方法？

例如，当我做这样的事情时：

private static final Date REQUEST_DATE = new Date();

@Mock
ConversionService conversionService;

@InjectMocks
ClaimRequestToClaimRequestTypeConverter converter = new ClaimRequestToClaimRequestTypeConverter();

@Before
public void setUp() throws Exception {
    MockitoAnnotations.initMocks(this);
}

@Test
public void convertTest() throws Exception {
    when(conversionService.convert(eq(REQUEST_DATE), eq(XMLGregorianCalendar.class))).thenCallRealMethod();

    ClaimRequest claim = new ClaimRequest();
    ClaimRequestType claimType = converter.convert(claim);

    verify(conversionService, times(3)).convert(eq(REQUEST_DATE), eq(XMLGregorianCalendar.class));
    verify(conversionService, times(2)).convert(isA(ClaimRequestAction.class), eq(ClaimRequestActionType.class));
    verifyNoMoreInteractions(conversionService);
}

我得到了：

org.mockito.exceptions.base.MockitoException: 
Cannot call real method on java interface. Interface does not have any implementation!
Calling real methods is only possible when mocking concrete classes.
//correct example:
when(mockOfConcreteClass.doStuff()).thenCallRealMethod();

Mockito版本：1.8.5

春季版：3.2.8