How to get / return the same passed argument / parameter from mock method

when(relatedProviderAddressAlternateIdentificationRepo.save(anyList())).thenAnswer(new Answer() {
            public Object answer(InvocationOnMock invocation) {
                return invocation.getArguments()[0];
            }
        });


Or

when(relatedProviderAddressAlternateIdentificationRepo.save(any(Class.class))).thenAnswer(new Answer() {
            public Object answer(InvocationOnMock invocation) {
                return invocation.getArguments()[0];
            }
        });


Class.class could be any custom class, eg: User.class