[jboss-dev-forums] [JBoss AS7 Development] - jboss7 quickstarts entitymanager injection question

robert walker [http://community.jboss.org/people/robertwalker] created the discussion "jboss7 quickstarts entitymanager injection question" To view the discussion, visit: http://community.jboss.org/message/635427#635427 -------------------------------------------------------------- Hi all, I am looking at the examples in jboss7 quickstarts , login and kithensink (ones that hit a DB) and wondering how jb7 knows which persistence unit to inject. for example if standalone.xml defines a few datasources  (like the default) ..... and say another named  "MyDataDSource" .... how does jboss know which one to inject when executing code like this from login quickstart's   ManagedBeanUserManager.java file @Inject private EntityManager userDatabase; No designation which PU to to inject,  I was thinking there would have to be code along the idea of the snippet below @PersistenceContext(unitName = "MyDataDSource") EntityManager em; I did read the "Chapter 5. CDI + JPA + EJB + JTA + JSF: Login quickstart" but was eagerly wanting to know how jboss knows which one to inject but didn't see it, which means it's so obvious that it does not need to be stated. So I realize i should know it this but I don''t. :-( I see the the pattern suggested by CDI is resource producers, but Resources.java has    // Expose an entity manager using the resource producer pattern    @SuppressWarnings("unused")    @PersistenceContext    @Produces    private EntityManager em; with no designation either can someone point me to a reesource to explain this a bit more thanks -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/635427#635427] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]