"If you're using the EntityManager API directly from a component in the web tier, we recommend that you avoid injecting entity managers because the EntityManager interface is not thread-safe. Instead,
you should use a JNDI lookup to grab an instance of a container-managed EntityManager."
The above paragraph is come from
EJB 3 in Action, I cannot understand it very much. Is there any difference between the injected EntityManager and the JNDI lookuped EntityManager? Or it just means if injecting entity manager to a
servlet, the entity manager should be an instance variable of that servlet so it is not
thread safe?
SCJP,SCWCD1.3,SCWCD1.4,SCJD,SCBCD5,SCEA5