public int add(Object o) {
        HollowTypeMapper typeMapper = getTypeMapper(o.getClass(), null, null);
        return typeMapper.write(o);
    }
@Test
    public void testPreassignedOrdinal() {
        HollowObjectMapper mapper = new HollowObjectMapper(writeStateEngine);
        TypeWithAssignedOrdinal o = new TypeWithAssignedOrdinal();
        o.__assigned_ordinal = 1;
        mapper.add(o);
        Assert.assertNotEquals(1, o.__assigned_ordinal);
    }