1. Esper
  2. ESPER-64

Example for running in J2EE container


    • Type: Improvement Improvement
    • Status: Closed Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 1.5
    • Fix Version/s: 1.0
    • Component/s: Examples
    • Labels:
    • Number of attachments :


      >If you have specific requirements on this chapter or wish >some samples please let us know.
      Yes, if you have some examples of Esper running in an EJB container I would be very interested. Our use case is the following: We have an J2EE-based self-service terminal managing system, which gets a lot of events from connected
      terminals (500 per second; e.g. ´paper low´, ´terminal out of order´) and we are correlating these events in the server to build up higher-level events. So for us it would be nice to use Esper in conjunction with our framework which is based mostly on stateless session beans and JMS messaging.

      >Esper is light-weight in terms of threads: each engine
      >instances starts 1 timer thread. However the engine can
      >also be externally timed and the timer thread disabled.
      >Thus Esper
      >engine threading should not interfere with J2EE
      >container threading.
      Sounds perfect. I think it is very important that Esper is fully J2EE compliant and not specific to any AppServer, so that it can be used in many scenarios and big applications.

      >Esper engine instances are not clusterable. That is, engine
      >state cannot be replicated within a J2EE application server
      >cluster if your server supports this configuration.
      No problem in a stateless application using JMS persistence.

      >If you are running inside an EJB container, using stateless
      >session EJBs, pooled EJB instances would need to share the
      >same Esper engine instance. The mechanism for sharing an
      >engine instance between EJBs, I think, would have to be via >static member variable, Singleton or possibly JNDI. For
      >servlets, the servlet context would seem to suit.
      An example of SLSBs using the Esper engine instance would be nice.


        Thomas Bernhardt added a comment -

        New terminal service case study added

        Thomas Bernhardt added a comment - New terminal service case study added


          • Assignee:
            Thomas Bernhardt
            Thomas Bernhardt


            • Created: