The code that unmarshals the XML responses from the deltacloud server is a mess. It is a mix of classic parsing and JAXB. Furthermore it has a lot of unsafe access (no null checks, no collection size checks etc.). It need serious refactoring.
Talking of design the code should be separated from the client and grouped along the elements it unmarschals. This would allow us to switch communication to json or any other encoded form if needed. The current implementation would now allow that.