David
The subProcessor beans can each run in their own thread. The EJB server
launches them. As to using the JDK 1.1+ event model, I see no clashes.
Tony
----
David Rauschenbach wrote:
>
> >> [tell] them to doWork with the given criteria
>
> Since EJB's are not allowed to make synchronization calls or start threads,
> these doWork methods must be called synchronously.
>
> >> and then listen for completion events from each worker bean
>
> Again, "listening for completion" eludes to using synchronization
> mechanisms being used in the evoker bean, which is ruled out by the spec in
> sec 16.4.
>
> I don't see room in the EJB spec for implementing the given solution. The
> invoker session bean (equiv.) could possibly be non-EJB, which leaves at
> least some of the system (the workers) in EJB. But that sounds lame, I
> wonder if this system isn't best left alone. Sounds like the RDBMS does all
> the hard work anyway.
>
> David
>
> Tony Holderith <[EMAIL PROTECTED]> on 03/11/99 03:18:51 PM
>
> Please respond to A mailing list for Enterprise JavaBeans development
> <[EMAIL PROTECTED]>
>
> To: [EMAIL PROTECTED]
>
> cc: (bcc: David Rauschenbach/ZLAND)
>
> Subject Re: Modeling an application with parallelism
> : using EJB
>
> Randy
>
> You may be able to create a bean for each subprocess, the them to doWork
> with
> the given criteria and then listen for completion events from each
> worker bean.
>
> I'm sure there will be interesting responses.
>
> Tony
> ----
>
> Mcree, Randy wrote:
> >
> > Dear EJB'ers,
> >
> > My colleagues and I were attempting to model a telco application using
> EJB.
> > The application currently runs on a CORBA server and makes heavy use of
> > threading to perform work in parallel. Because of the programming
> > limitations in EJB (cf section 16.4) we are not sure that we can model
> this
> > application in EJB?.
> >
> > This application creates customer's phone bills. For each customer, the
> bill
> > consists of the aggregation of the costs over all phones during the
> billing
> > period. The costs are contained in call detail records. These records are
> > stored in a partitioned database, spread across many physical disks, in
> > order to support simultaneous queries. The current application creates
> > subprocesses which more or less simultaneously queries all of a
> customer's
> > phones for records within a given time span. The result of each
> subprocess
> > is asynchronously returned to an aggregation function which waits for all
> > subprocesses to "report in". It seems like this aggregation function
> cannot
> > be implemented as an EJBean because, as a bean, it cannot spawn threads,
> > which is key to creating the necessary parallelism. The parallelism is
> > necessary in order to complete the bill in a reasonable time. Note that
> the
> > hardware of the system is set up for this task: multiple disks, multiple
> > cpus, multiple paths from cpu to disk...we need the software to take
> > advantage of these capabilities.
> >
> > If we stick the aggregation function into, say, a CORBA server, then the
> > question becomes, why EJB? There is a lot of business logic at that point
> > (tax calculations, customized customer items, etc.) that seem beneficial
> to
> > express within a bean.
> >
> > Thanks in advance for any insights...
> >
> > Randy McRee
> > Sr. Software Developer
> > Tandem division of COMPAQ
> >
> >
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>
> --
> Tony Holderith | Interactive Business Solutions
> [EMAIL PROTECTED] | NetCentric Solutions
> http://www.interactivebusiness.com | Business Objects
> voice: 310.414.6760 | fax: 310.414.6759
>
> Don't connect to the Internet - be there. IBS
>
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> To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
> of the message "signoff EJB-INTEREST". For general help, send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
>
> ===========================================================================
> To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
> of the message "signoff EJB-INTEREST". For general help, send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
--
Tony Holderith | Interactive Business Solutions
[EMAIL PROTECTED] | NetCentric Solutions
http://www.interactivebusiness.com | Business Objects
voice: 310.414.6760 | fax: 310.414.6759
Don't connect to the Internet - be there. IBS
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff EJB-INTEREST". For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".
