MathGroup Archive 2005

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Re: JLink discover and link to an already running kernel from a Java App

  • To: mathgroup at smc.vnet.net
  • Subject: [mg61689] Re: [mg61651] Re: JLink discover and link to an already running kernel from a Java App
  • From: j michopoulos <john.michopoulos at nrl.navy.mil>
  • Date: Wed, 26 Oct 2005 01:01:42 -0400 (EDT)
  • References: <43570892.3010702@nrl.navy.mil> <djd013$erb$1@smc.vnet.net> <200510250107.VAA16807@smc.vnet.net>
  • Reply-to: john.michopoulos at nrl.navy.mil
  • Sender: owner-wri-mathgroup at wolfram.com

Dear Jens,

Please see below

Jens-Peer Kuska wrote:
> Hi,
> 
> that would be a great idea. Say, you have an 
> Mathematica Kernel that
> does a 3 week symbolic computation and during this time
> several Java application connect to the kernel and hinder
> it to do it's work.

Though what you describe is a possible scenario where obviously what I 
asked does not provide bebefits (and is certainly NOT what I had in 
mind) there are many other scenarios that what I asked is terribly 
important: for instance, the running kernel gets real-time data from a 
hardware data-acquisition device controled by the java application (that 
seeks to connect to that kernel) and therefore symbolic computation 
performance is NOT as important. Anotehr example may be when the running 
kernel needs to exchange expressions with another "legacy" application 
wrapped by Java NAtive Interface (JNI) API enabled Java wrapper and 
therefore play an alternating rome of client-server for and with another 
program. Many other examples can be also specified when you want the 
running kernel to depent on other applications in order to achieve its 
specifications.

> 
> Your Java application may create a link

OK how can one create a link WITHOUT spawning a new kernel? How this 
Java app will expose its namespace to the kernel?

> and you can take a running kernel and tell the kernel
> to connect to the link generated by your Java 
> application.

That would be ok if I had access of the running kernel through some 
other front-end application which is NOT an option in my USE CASE (ala UML)

The idea is that the running kernel does not (and cannot apriori) know 
of the java app and the java app does not know of the running kernel's 
presence. The idea is how one can discover the other by running some 
code within its runtime env? This is supposed to happen in an 
asynchronous and agnostic cooperating processes semantic base fashion.

If you know of any examples along these lines I would enormously 
appreciate your help.

Thanks greatly for responding to my request,

-john michopoulos


> 
> Regards
>   Jens
> 
> "j michopoulos" <john.michopoulos at nrl.navy.mil> 
> schrieb im Newsbeitrag 
> news:djd013$erb$1 at smc.vnet.net...
> | Another variation of my previous posting (see 
> below) can be expressed as
> | follows:
> |
> | Is it possible to detect from within a Java app 
> if a Mathematica Kernel
> | is already running and after that connect to it? 
> If yes, how?
> |
> | I would enormously appreciate it if somebody 
> could point me to an
> | example or document that will shed some light on 
> this, or,
> | alternatively, share his/her experience on the 
> subject.
> |
> | Thanks greatly,
> |
> | -john michopoulos
> | ========================================
> | John G. Michopoulos, Ph. D.
> | Naval Research Laboratory,
> | Center of Computational Material Science
> | Special Projects Group, Code 6390.2
> | Computational Multiphysics Systems Lab.
> | 4555 Overlook Ave. SW, Washington DC 20375
> | tel.202.767.2189
> | e-mail: john.michopoulos at nrl.navy.mil
> |
> | j michopoulos wrote:
> | > While one can use the ShareKernel[] call 
> within mathematica to share one
> | > kernel with multiple front-ends as explained 
> in
> | > 
> http://support.wolfram.com/mathematica/mathlink/general/sharekernel.html,
> | > I cannot find anywhere any info how to share a 
> kernel that was started
> | > by one instance of a Java App front end via a 
> standard
> | > MathLinkFactory.createKernelLink(...) call, 
> and then be discovered by
> | > another application or instance of the 
> previous App to continue
> | > expression evaluation under the original 
> kernel.
> | >
> | > I have created Mathematica actors for the 
> Ptolemy-II system
> | > (http://ptolemy.eecs.berkeley.edu/ptolemyII/) 
> that open and close the
> | > kernel around the designated expression 
> evaluation for the purpose of
> | > automating theory generation, but now I need a 
> variant of these actors
> | > that exploit the same environment and that 
> requires that they both
> | > access the same Kernel which makes it a 
> special case of he problem I
> | > described in the previous paragraph.
> | >
> | > I would enormously appreciate any help along 
> these lines..
> | >
> | >
> | > -- john m.
> | > ========================================
> | > John G. Michopoulos, Ph. D.
> | > Naval Research Laboratory,
> | > Center of Computational Material Science
> | > Special Projects Group, Code 6390.2
> | > Computational Multiphysics Systems Lab.
> | > 4555 Overlook Ave. SW, Washington DC 20375
> | > tel.202.767.2189
> | > e-mail: john.michopoulos at nrl.navy.mil
> | >
> | 
> 
> 


  • Prev by Date: Re: Language vs. Library why it matters
  • Next by Date: Re: aggregation of related elements in a list
  • Previous by thread: Re: JLink discover and link to an already running kernel from a Java App
  • Next by thread: Keyboard Shortcuts Cell Menu Mac