5 Replies Latest reply on Mar 6, 2003 10:40 AM by mclaugs

    JSR77 doubts

    ivrajesh

      Hi,

      I have some doubts to be clarified.

      1)In JBoss3_0_4 i tried to stop one managed object(jboss.management.single:J@EEApplication=
      ,J2EEServer=Single,j2eeType=ResourceAdapterModule,name=jms-ra.rar) which has it's StateManageable object true.Then i got the following exception

      21:12:32,155 ERROR [ResourceAdapterModule] Stop of Resource Adapter Module failed
      MBeanException: No operations exposed for RARDeployment
      at org.jboss.resource.RARDeployment.invoke(RARDeployment.java:70)
      at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:517)
      at org.jboss.management.j2ee.ResourceAdapterModule.mejbStop(ResourceAdapterModule.java:362)

      Before stopping the managed object the State attribute of that managed object showed 0.After invoking mejbStop it was changed to 2 and also with the above said exception. Is it a issue?.

      2)We can create a Listener for the MangedObjects Notifications. As of now i have seen that the Notifications are emitted for the
      State chage of the Manged Objets(starting,running,stopping etc).I could see the the spec JSR77 spec says more about creating listeners for the Manged Objects. If i want to add one more event to my Managed Object on some condtion how i can i do it?.

      3)Some of the Manged Objects has it's StatisticProvider and StateManageable attributes true and some are false. In what perspective it's decided. can client have any control over it?.

      Please your help is appreciated.

      Thanks,
      Rajesh I.V

        • 1. Re: JSR77 doubts
          mclaugs

          The JSR-77 implementation in JBoss before version 3.2 has problems with the mapping of service state to JSR-77 state.

          based on the exception you are getting the ResourceAdapterModule should not be state manageable, since the JBoss service that it represents does not support it. State Management is something that is still being looked at. What needs to be determined is what effect does stopping a service have on JBoss.

          I would not consider this an issue since the JSR-77 support in versions of JBoss before 3.2 was not complete. If you use JBoss 3.2+ and you are able to execute stop on a state manageable object and it throws an exception, I would consider that a problem.

          Can you describe what events you would add that would send notifications from the JSR-77 management system.

          The Statistic Provider and State Manageable attributes are provided to inform a client that the management object that is being looked at does or does not support state management or does or does not provide statistics as defined by the JSR-77 specification.

          Since JSR-77 management objects are a server component a client has no control over this, to support state management the underlining JBoss services must understand what state management means. The same is true for providing statistics, the management object need to get the statistics information from somewhere, so therefore the JBoss services need to know how to provide them.

          Does this answer you questions?

          Scott McLaughlin

          • 2. Re: JSR77 doubts
            mclaugs

            The JSR-77 implementation in JBoss before version 3.2 has problems with the mapping of service state to JSR-77 state.

            based on the exception you are getting the ResourceAdapterModule should not be state manageable, since the JBoss service that it represents does not support it. State Management is something that is still being looked at. What needs to be determined is what effect does stopping a service have on JBoss.

            I would not consider this an issue since the JSR-77 support in versions of JBoss before 3.2 was not complete. If you use JBoss 3.2+ And you are able to execute stop on a state manageable object and it throws an exception, I would consider that a problem.

            Can you describe what events you would add that would send notifications from the JSR-77 management system.

            The Statistic Provider and State Manageable attributes are provided to inform a client that the management object that is being looked at does or does not support state management or does or does not provide statistics as defined by the JSR-77 specification.

            Since JSR-77 management objects are a server component a client has no control over this, to support state management the underlining JBoss services must understand what state management means. The same is true for providing statistics, the management object need to get the statistics information from somewhere, so therefore the JBoss services need to know how to provide them.

            Does this answer you questions?

            Scott McLaughlin

            • 3. Re: JSR77 doubts
              mclaugs

              The JSR-77 implementation in JBoss before version 3.2 has problems with the mapping of service state to JSR-77 state.

              based on the exception you are getting the ResourceAdapterModule should not be state manageable, since the JBoss service that it represents does not support it. State Management is something that is still being looked at. What needs to be determined is what effect does stopping a service have on JBoss.

              I would not consider this an issue since the JSR-77 support in versions of JBoss before 3.2 was not complete. If you use JBoss 3.2+ And you are able to execute stop on a state manageable object and it throws an exception, I would consider that a problem.

              Can you describe what events you would add that would send notifications from the JSR-77 management system.

              The Statistic Provider and State Manageable attributes are provided to inform a client that the management object that is being looked at does or does not support state management or does or does not provide statistics as defined by the JSR-77 specification.

              Since JSR-77 management objects are a server component a client has no control over this, to support state management the underlining JBoss services must understand what state management means. The same is true for providing statistics, the management object need to get the statistics information from somewhere, so therefore the JBoss services need to know how to provide them.

              Does this answer you questions?
              Scott McLaughlin

              • 4. Re: JSR77 doubts
                ivrajesh

                Hi,

                Thanks for your reply.It is really useful to me.When will JBoss3.2 be released?.

                Ok what i meant by the addition of an event form a managed object is, for e.g we assume, there is one ejb and state manageable and event provider model are supported for that.So the listener may get the state change events of that ejb. If i want to add one more event to my managed object ie if one particular business method in that EJB is invoked then a event has to be sent.Then how to make the ejb a broadcaster of that event and how to do it.

                I have own more doubt.The application server is maintaining a J2EE model as per JSR77 standard.With that it forms the hierachy for the various resources and applications in that appserver. Can a customer make his own hirearchial model for his appliactions.It means can he make his own managed objects. If so how can he do that and how JBoss supports for it.

                Eagerly awaiting yor reply.

                Thanks,
                Rajesh I.V

                • 5. Re: JSR77 doubts
                  mclaugs

                  Currently Release Candidate 3 can be downloaded from SourceForge http://sourceforge.net/projects/jboss/

                  Since JSR-77 Management object provide a management view of the deployed services and applications in order to add extra notifications they would need to be added in the JBoss server. Because of this it is not possible to add from an application. The spec only requires the notification of state management events, but allows for additional vendor specific event to be broadcast.

                  Can you give me more detail on the project you are working on along with why you would like to listen for notifications of EJB method invocations?

                  JSR-77 Management objects are defined at the application server level of the J2EE environment. The JSR-77 Spec defines the hierarchy, this hierarchy can be extended but MUST be supported exactly as specified in the JSR-77 specification. an Example of extending this hierarchy, JBoss defines a j2eeType of ServiceModule which provides a jsr-77 management object for all .sar archives deployed in the JBoss sever. This j2eeType is a vendor specific extension and would not likely be support by another application server vendor.

                  As for creating a jsr-77 management object for an application this is not possible. What I would suggest is you look at creating MBeans for you application this can be used to give your application JMX manageability though they would not be jsr-77 management object.

                  Other questions or doubts post them, they help me to determine what is missing from the jsr-77 specification and can lead to the possibility of some nice extensions to the specification the JBoss implementation.

                  Scott McLaughlin