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EJB design: JMS, MDBs & Servlets

  1. JMS, MDBs & Servlets (1 messages)

    Hi People,

    I have a question... I read a recent post on theserverside.com about JMS and I am keen to implement it in my applications. But I have a few questions:

    I need to write a servlet (in application 1) that publishes a message to a topic. And other servlets (in applications 2 and 3) to subscribe to this topic to recieve the message. The subscribers subscribe when applications 2 and 3 start up.

    Im using servlets because it would be overkill to use MDBs. (since this is demo/proof of concept). My question is (about scalability I guess): In this scenario, are there any disadvantages of using servlets instead of MDBs (as subscribers)?

    And also if there aren't any (disadvantages) why would anyone uses MDBs when servlets are easier to code (Not that MDBs are that complex but deployment, appserver problems!!!, etc could slow you down) and if messages can be transfered between applications without them?

    Cheers

    Smythe

  2. JMS, MDBs & Servlets[ Go to top ]

    You need to use MDB's if you want to receive messages asynchronously, whereas servlets/Session EJB can be used to pick-up/wait-for messages in the queue or topic.

    HTH,
    -Sri