3 Replies Latest reply: Jan 21, 2008 3:19 AM by 807557 RSS

    Documentation on available "happenings" for RTSJ 2?

    807557
      Hi,

      This may be documented somewhere, but I haven't been able to find anything specific -

      The bindTo() method on the AsyncEvent object takes a String as the specifier of the "happening" that you're binding to. Is there a documented list somewhere of the strings that define the available happenings in the Sun RTSJ 2 release? Is it possible to query the VM at runtime and retrieve a list of all the strings that define the happenings supported by that VM?

      Thanks,
      David.
        • 1. Re: Documentation on available "happenings" for RTSJ 2?
          807557
          There is no list because Java RTS does not support any external "happenings" - these things are VM specific and so would be documented in VM specific documentation.

          There is no API for querying the available set of happenings in a VM. The reason being there is no pre-defined set of happenings, so no standardized names for which to ask, or report.

          The main external events of interest are signals, and these can be interacted with using the PosixSignalHandler class.

          David Holmes
          • 2. Re: Documentation on available "happenings" for RTSJ 2?
            807557
            these things ... would be documented in VM specific documentation
            I have the Sun documentation for the Sun VM. And I can't find anything that lists the happenings that Sun supports (other than the Posix signal handlers). If that's all there is at the moment, then fine. But it's not clear from the documentation at the moment. A line in the docs that said "The Sun VM does not define any external happenings other than the following Posix signal handlers" would be more explicit, and would have saved me from looking for things that might not even be there :-)

            Again, if this is documented somewhere, and I'm just being dim, then a pointer to the correct source would be appreciated.

            There is no API ... no pre-defined set of happenings ... no standardized names for which to ask
            I take your point. But the regular VM allows you to do things like query the list of Memory Managers and Memory Pools and return their names - and as far as I am aware, the names for those things aren't standardised. So it could be done. The VM is generally very good about providing quite rich information on the runtime environment, which is why I thought there might be a simple JMX-style api to list the supported happenings. More idle curiosity than anything else :-)

            Thanks for your reply.

            David.
            • 3. Re: Documentation on available "happenings" for RTSJ 2?
              807557
              david.dickinson wrote:
              these things ... would be documented in VM specific documentation
              I have the Sun documentation for the Sun VM. And I can't find anything that lists the happenings that Sun supports (other than the Posix signal handlers). If that's all there is at the moment, then fine. But it's not clear from the documentation at the moment. A line in the docs that said "The Sun VM does not define any external happenings other than the following Posix signal handlers" would be more explicit, and would have saved me from looking for things that might not even be there :-)

              Again, if this is documented somewhere, and I'm just being dim, then a pointer to the correct source would be appreciated.
              There is no explicit documentation, I'll make a note to add it to one of the docs.

              >
              There is no API ... no pre-defined set of happenings ... no standardized names for which to ask
              I take your point. But the regular VM allows you to do things like query the list of Memory Managers and Memory Pools and return their names - and as far as I am aware, the names for those things aren't standardised. So it could be done. The VM is generally very good about providing quite rich information on the runtime environment, which is why I thought there might be a simple JMX-style api to list the supported happenings. More idle curiosity than anything else :-)
              I meant from the perspective of the RTSJ, there's no API defined.

              If we supported happenings then we could of course make them discoverable/accessible via an appropriate management bean.

              David Holmes