Hello everyone,

 I am working on a project where I am using a C++ framework and API to
create a game agent. My agent has to be flexible so it can react to/predict
events that occur inside the game environment, Jess has the kind
of flexibility that I need for my agent to be good,  but I am having trouble
connecting to Jess from C++ and that is where I was hoping someone could
help me out.

*What I am doing right now*
I have a C++ program that starts a Java Virtual Machine and searches for a
Java class file name "TestJNIJessInvoke"

Inside of "TestJNIJessInvoke.java" I define a simple function in Jess, and
try to call that function then print the result
import jess.*;
public class TestJNIJessInvoke
    public static void main(String[] args) throws JessException
Rete r = new Rete();
r.executeCommand("(deffunction square (?n) (return (* ?n ?n)))");
Value v = r.executeCommand("(square 3)");


But when I try to compile and link the C++ file with:
*cl *
*   -I"C:\Program Files\Java\jdk1.7.0\include" *
*   -I"C:\Program Files\Java\jdk1.7.0\include\win32" *
*   TestJNIJessInvoke.cpp *
*   -link "C:\Program Files\Java\jdk1.7.0\lib\jvm.lib"*
I get a class loader exception:
*Exception in thread "main" java.lang.NoClassDefFoundError: jess/Rete*
*        at TestJNIJessInvoke.main(TestJNIJessInvoke.java:6)*
*Caused by: java.lang.ClassNotFoundException: jess.Rete*
*        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)*
*        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)*
*        at java.security.AccessController.doPrivileged(Native Method)*
*        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)*
*        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)*
*        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)*
*        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)*
*        ... 1 more*
Exception in thread "main" java.lang.NoClassDefFoundError: jess/Rete
        at TestJNIJessInvoke.main(TestJNIJessInvoke.java:6)
Caused by: java.lang.ClassNotFoundException: jess.Rete
        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
        ... 1 more


1) Is there some other directory that I am supposed to be including that has
the .class files for Jess? Right now all I am including is jess.jar
2) Is the general design I have a good idea? or is there a better way to
facilitate communication between Jess and C++?

Hunter McMillen

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