public boolean add(final Integer element)
    {
        return addInt(null == element ? nullValue : element);
    }
@Test
    void shouldEqualGenericList()
    {
        final int count = 7;
        final List<Integer> genericList = new ArrayList<>();

        for (int i = 0; i < count; i++)
        {
            list.add(i);
            genericList.add(i);
        }

        list.add(null);
        genericList.add(null);

        assertEquals(list, genericList);
    }