Even I have same doubt "Cade & Sheil example in the 3rd SD "Email Server" has been added and "sendMessage" is called on the "Email Server". Should it there be EmailDAO instead of external system? "
Because we are referencing webservice into session bean by @WebServiceRef annotation, hence I dont think there is any scope of introducing DAO, but then any external datasource should be accessed using DAO. I am stuck in this point.
Can someone please clarify?
subject: Showing an external system in Sequence Diagram