Can someone please clarify the meaning of this paragraph taken from specs..
A message-driven bean instance has no state for a specific client. However, the instance variables of the message-driven bean instance can contain state across the handling of client messages. Examples of such state include an open database connection and a reference to an enterprise bean.
This portion is confusing for me "However, the instance variables of the message-driven bean instance can contain state across the handling of client messages"
its the same for stateless session benas.Please clarify with an example if possible..
It means that a MDB or a SB Stateless can have instance variable (connections, counters, etc.). Those instance variable are the State of the EJB.
But they don't maintain conversational state with a specific client. No conversational state means that if you receive 2 messages o 2 calls to a SB Stateless, you can't be sure that the same instance of EJB will serve you.