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EJB 2.0 Drawbacks

  • Complex Products
  • Unmaintainable System
  • Non-portable, frame-work committed business components
  • Unpredictable System
  • Why EJB 2.0 is complex / complicated?
    • Session bean - to write say hello method

      in EJB 2.x, you need to write
      home interface
      component interface
      bean

      in EJB 3.x, you need to write
      interface (with annotation)
      bean (with annotation)

      EJB 2.x; lookup is the only way to get server object/resource
      EJB 3; DI (dependency injection) & lookup are the available way


      there are more points. But basically, with EJB 3 responsibility of container is heavy & responsibility of developer is light weight; so that development is less & maintenance is easy.
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