Why Mockito type matchers match unrelated objects?

Question

I need a behaviour of a mock to depend on argument type. I've tried to use Matchers.any(Class<>) to provide two behaviours:

public class MockitoTest {
    public interface ToMock {
        String accept(Object object);
    }
    interface A {
    }
    interface B {
    }
    @Test
    public void doAnswer() {
        ToMock mock = Mockito.mock(ToMock.class);

        Mockito.doReturn("A received").when(mock).accept(Matchers.any(A.class));
        Mockito.doReturn("B received").when(mock).accept(Matchers.any(B.class));

        Assert.assertEquals("A received", mock.accept(new A() {}));
        Assert.assertEquals("B received", mock.accept(new B() {}));
    }
}

Test fails with:

org.junit.ComparisonFailure: expected:<[A] received> but was:<[B] received>

What am I doing wrong?

Mockito version 1.9.5

Answer 1

This is expected behaviour. According to the documentation of Matchers.any(Class)

Any kind object, not necessary of the given class. The class argument is provided only to avoid casting.