At line 3 and 4 in the OrderDriver class you look only for the static result so you have line 2 and line 4,5 (""+"u" = u) . This is duplicated so the output till now is :
You have an initalization of the Order object.
First use the static reference and then the initialization blocks so result is "ucr".
Another Object is created so you concatenate to result the initalization blocks "cr". Result from this two initalization is ucrcr.