public class JMockitTest {
    @Injectable
    private Manager manager;
    @Injectable
    private User user;

    interface Manager {
        <T extends Entity> T find(Class<T> clazz);
    }

    interface Entity {
    }

    static class User implements Entity {
    }

    @Test
    public void test() throws Exception {
        new Expectations() {{
            manager.find(User.class);
            result = user;
        }};
        final Entity actual = manager.find(User.class);
        assertSame(actual, user);
    }
}