[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

embedding a JVM into octave

From: Al Niessner
Subject: embedding a JVM into octave
Date: Thu, 07 Apr 2005 09:40:56 -0700

Sometimes computers behave and sometimes they do not. In this case, they
definitely are not. I have a chunk of Java code that I use for talking
to and controlling hardware. This hardware is distributed over some set
of computers on a private network. I then use XML to describe the
hardware layout to the Java. Now, I would like to command this hardware
in some way that makes with Octave as my math engine (think labview kind
of thing). The communications is non-trivial because the system is
distributed but works well (it has been tested) using the Java I have.
What I would like to now is call this Java code using octave. I did not
think it would be that hard really, but it is turning out to be a lot
more difficult than I had suspected.

To start with, I wrote a library (commandInterface.h is attached) that
creates a JVM. It then looks up the necessary classes and methods it
needs to do the communications. I wanted to test this quickly so I wrote
a small C++ program to do this (commandInterfaceTest.cxx is attached).
It works just fine. I then wrote the first of many OCT files (
is attached) and it does not work. Why? All inputs are the same and
absolute file names are used in the class path. Is Octave doing
something that I need to know about? The JVM starts, but I cannot find
any of the classes that I need and they are all in the class path as I
can prove with commandInterfaceTest. This leaves me with just the option
that Octave is somehow interfering with the JVM, but I do not know how.
Any and all help is appreciated.

The error I get is: "Can't find the class

It is easy to tell from reading the initialization function (
is attached) that the JVM should have started successfully and the
environment is not NULL. If it were, then I would expect a segmentation
fault not a failed class name look-up.

Again, any and all help is much appreciated.

Al Niessner

All opinions stated above are mine and do not necessarily reflect those
of JPL or NASA.

|  dS  | >= 0

Attachment: commandInterface.h
Description: Text Data

Attachment: commandInterfaceTest.cxx
Description: Text Data

Description: Text Data

Attachment: initFunc.cxx
Description: Text Data

reply via email to

[Prev in Thread] Current Thread [Next in Thread]