Mockito call a method on a parameter of a mocked method

Question

I am just starting with Mockito and I just want to do something like :

public class Test {     
    public void clearList(List l){
        doVeryLOOOONGDatabaseCallll();
        l.clear();
        return;
    }
}

/// ... 
Test test = mock(Test.class);
Mockito.when(test.clearList(any(List.class))).then( l => l.clear());

Have some hint to do the trick? Thank you for your help!

Answer 1

Something like this should do it (not tested):

doAnswer(new Answer() {
    public Object answer(InvocationOnMock invocation) {
        Object[] args = invocation.getArguments();
        List<?> list = (List<?>) args[0];
        list.clear();
        return null;
    }
}).when(test).clearList(any(List.class));