Re: JESS: Call Jess from C++ via JNI
Well I am trying to create an agent to compete in the Starcraft AI
competition for next year, the API that the agents all use is called BWAPI:
http://code.google.com/p/bwapi/, but this is also a standard library that
some of the agents use that would be really useful for for my agent called
BWSAL: http://code.google.com/p/bwsal/. Anyway there is a native interface
that someone created for BWAPI, which I was planning on using in my code, so
my plan was to create a native interface for BWSAL, that way I could do all
the Jess interaction inside of Java, then call associated methods in C++ via
JNI. Does this sound far-fetched?
On Thu, Sep 29, 2011 at 5:10 PM, Socrates Frangis soc.fran...@gmail.comwrote:
What framework are you using? Curious to see how it is invoking JNI.
using this I think I can only interact with Jess in my Java program then
pass data from my Java code to C++
-Unless your framework has an API supporting JESS specifically, i doubt
that is the case. It should be providing a 'simpler' implementation to
access your java classes but that would just eliminate the cryptic path
declaration and still give you an interface to what youre playing with.
Overall opinion, given the chance that your framework may inhibit full
controll of the Rete engine or using JESS (and for the learning experience)
i would recommend sticking with your current implementation. Rule engines
require precise attention to detail and i wouldn't risk the chance of losing
fidelity.
On Wed, Sep 28, 2011 at 2:22 PM, Hunter McMillen mcmil...@gmail.comwrote:
Sorry to pester you with more questions.
The way I am currently doing things in invoking a JVM from C++ to call
Java code that calls/interacts with Jess code, but it turns out that someone
has actually created a java native interface for the api/framework I am
using to make my agent, using this I think I can only interact with Jess in
my Java program then pass data from my Java code to C++, I was wondering if
you thought this would be a better solution than invoke a JVM from C++
Thanks
Hunter
On Tue, Sep 27, 2011 at 12:03 PM, Friedman-Hill, Ernest
ejfr...@sandia.gov wrote:
**
This is all perfectly reasonable so far. When you create the JVM you'll
need to tell it where jess.jar is, along with any other jars you use, with
the -cp flag or the java.class.path property.
Once you have this working, you'll presumably want to connect things a
little more tightly. You can use the JNI API to write the equivalent of your
three-line main() in C++ pretty easily; you'll want to put together a C++
version executeCommand() that controls the Rete instance, passes a script
along, executes it, and gets the Value back, decoding it as needed.
--
*From:* owner-jess-us...@sandia.gov [mailto:owner-jess-us...@sandia.gov]
*On Behalf Of *Hunter McMillen
*Sent:* Monday, September 26, 2011 8:51 PM
*To:* jess-users
*Subject:* JESS: Call Jess from C++ via JNI
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));
System.out.println(v.intValue(r.getGlobalContext()));
}
}
But when I try to compile and link the C++ file with:
*cl *
* -IC:\Program Files\Java\jdk1.7.0\include *
* -IC:\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*
*
*
RE: JESS: Call Jess from C++ via JNI
To restate: you have three libraries you want to use:
- One (Jess) is written in Java;
- One (BWAPI) can be accessed from Java by using an existing JNI interface,
- And the third (BWSAL) is currently available only in native code.
Your current plan is to write a JNI wrapper for some or all of BWSAL and write
your application in Java. This makes perfect sense to me.
It might be even easier to use JNA (http://jna.java.net/) instead of writing a
specific wrapper, but that depends on various details. Worth looking at, anyway.
From: owner-jess-us...@sandia.gov [mailto:owner-jess-us...@sandia.gov] On
Behalf Of Hunter McMillen
Sent: Saturday, October 01, 2011 12:52 PM
To: jess-users
Subject: Re: JESS: Call Jess from C++ via JNI
Well I am trying to create an agent to compete in the Starcraft AI competition
for next year, the API that the agents all use is called BWAPI:
http://code.google.com/p/bwapi/, but this is also a standard library that some
of the agents use that would be really useful for for my agent called BWSAL:
http://code.google.com/p/bwsal/. Anyway there is a native interface that
someone created for BWAPI, which I was planning on using in my code, so my plan
was to create a native interface for BWSAL, that way I could do all the Jess
interaction inside of Java, then call associated methods in C++ via JNI. Does
this sound far-fetched?
On Thu, Sep 29, 2011 at 5:10 PM, Socrates Frangis
soc.fran...@gmail.commailto:soc.fran...@gmail.com wrote:
What framework are you using? Curious to see how it is invoking JNI.
using this I think I can only interact with Jess in my Java program then pass
data from my Java code to C++
-Unless your framework has an API supporting JESS specifically, i doubt that is
the case. It should be providing a 'simpler' implementation to access your
java classes but that would just eliminate the cryptic path declaration and
still give you an interface to what youre playing with.
Overall opinion, given the chance that your framework may inhibit full controll
of the Rete engine or using JESS (and for the learning experience) i would
recommend sticking with your current implementation. Rule engines require
precise attention to detail and i wouldn't risk the chance of losing fidelity.
On Wed, Sep 28, 2011 at 2:22 PM, Hunter McMillen
mcmil...@gmail.commailto:mcmil...@gmail.com wrote:
Sorry to pester you with more questions.
The way I am currently doing things in invoking a JVM from C++ to call Java
code that calls/interacts with Jess code, but it turns out that someone has
actually created a java native interface for the api/framework I am using to
make my agent, using this I think I can only interact with Jess in my Java
program then pass data from my Java code to C++, I was wondering if you thought
this would be a better solution than invoke a JVM from C++
Thanks
Hunter
On Tue, Sep 27, 2011 at 12:03 PM, Friedman-Hill, Ernest
ejfr...@sandia.govmailto:ejfr...@sandia.gov wrote:
This is all perfectly reasonable so far. When you create the JVM you'll need to
tell it where jess.jar is, along with any other jars you use, with the -cp
flag or the java.class.path property.
Once you have this working, you'll presumably want to connect things a little
more tightly. You can use the JNI API to write the equivalent of your
three-line main() in C++ pretty easily; you'll want to put together a C++
version executeCommand() that controls the Rete instance, passes a script
along, executes it, and gets the Value back, decoding it as needed.
From: owner-jess-us...@sandia.govmailto:owner-jess-us...@sandia.gov
[mailto:owner-jess-us...@sandia.govmailto:owner-jess-us...@sandia.gov] On
Behalf Of Hunter McMillen
Sent: Monday, September 26, 2011 8:51 PM
To: jess-users
Subject: JESS: Call Jess from C++ via JNI
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));
System.out.println(v.intValue(r.getGlobalContext()));
}
}
But when I try to compile and link the C++ file with:
cl
-IC:\Program Files\Java\jdk1.7.0\include
-IC:\Program Files
Re: JESS: Call Jess from C++ via JNI
What framework are you using? Curious to see how it is invoking JNI.
using this I think I can only interact with Jess in my Java program then
pass data from my Java code to C++
-Unless your framework has an API supporting JESS specifically, i doubt that
is the case. It should be providing a 'simpler' implementation to access
your java classes but that would just eliminate the cryptic path declaration
and still give you an interface to what youre playing with.
Overall opinion, given the chance that your framework may inhibit full
controll of the Rete engine or using JESS (and for the learning experience)
i would recommend sticking with your current implementation. Rule engines
require precise attention to detail and i wouldn't risk the chance of losing
fidelity.
On Wed, Sep 28, 2011 at 2:22 PM, Hunter McMillen mcmil...@gmail.com wrote:
Sorry to pester you with more questions.
The way I am currently doing things in invoking a JVM from C++ to call Java
code that calls/interacts with Jess code, but it turns out that someone has
actually created a java native interface for the api/framework I am using to
make my agent, using this I think I can only interact with Jess in my Java
program then pass data from my Java code to C++, I was wondering if you
thought this would be a better solution than invoke a JVM from C++
Thanks
Hunter
On Tue, Sep 27, 2011 at 12:03 PM, Friedman-Hill, Ernest
ejfr...@sandia.gov wrote:
**
This is all perfectly reasonable so far. When you create the JVM you'll
need to tell it where jess.jar is, along with any other jars you use, with
the -cp flag or the java.class.path property.
Once you have this working, you'll presumably want to connect things a
little more tightly. You can use the JNI API to write the equivalent of your
three-line main() in C++ pretty easily; you'll want to put together a C++
version executeCommand() that controls the Rete instance, passes a script
along, executes it, and gets the Value back, decoding it as needed.
--
*From:* owner-jess-us...@sandia.gov [mailto:owner-jess-us...@sandia.gov]
*On Behalf Of *Hunter McMillen
*Sent:* Monday, September 26, 2011 8:51 PM
*To:* jess-users
*Subject:* JESS: Call Jess from C++ via JNI
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));
System.out.println(v.intValue(r.getGlobalContext()));
}
}
But when I try to compile and link the C++ file with:
*cl *
* -IC:\Program Files\Java\jdk1.7.0\include *
* -IC:\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
*Questions*
1) Is there some other
Re: JESS: Call Jess from C++ via JNI
Thanks a lot! That was exactly what was going wrong. Hunter On Tue, Sep 27, 2011 at 1:31 PM, Friedman-Hill, Ernest ejfr...@sandia.govwrote: ** The problem is here. The Java classpath doesn't list directories in which jar files can be found, but rather, the jar files themselves. The argument should be, e.g., -Djava.class.path=./jess.jar. * options[0].optionString = (char*)-Djava.class.path=.; //the current directory is where jess.jar is also*
Re: JESS: Call Jess from C++ via JNI
Thanks Ernest! I was on the phone call, so you overran me. :-) Dusan Sormaz On 9/27/2011 1:31 PM, Friedman-Hill, Ernest wrote: The problem is here. The Java classpath doesn't list directories in which jar files can be found, but rather, the jar files themselves. The argument should be, e.g., -Djava.class.path=./jess.jar. * options[0].optionString = (char*)-Djava.class.path=.; //the current directory is where jess.jar is also* -- *** * Dusan Sormaz, PhD, Associate Professor * Ohio University * Department of Industrial and Systems Engineering * 284 Stocker Center, Athens, OH 45701-2979 * phone: (740) 593-1545 * fax: (740) 593-0778 * e-mail: sor...@ohio.edu * url: http://www.ohio.edu/people/sormaz ***
Re: JESS: Call Jess from C++ via JNI
Sorry to pester you with more questions.
The way I am currently doing things in invoking a JVM from C++ to call Java
code that calls/interacts with Jess code, but it turns out that someone has
actually created a java native interface for the api/framework I am using to
make my agent, using this I think I can only interact with Jess in my Java
program then pass data from my Java code to C++, I was wondering if you
thought this would be a better solution than invoke a JVM from C++
Thanks
Hunter
On Tue, Sep 27, 2011 at 12:03 PM, Friedman-Hill, Ernest
ejfr...@sandia.govwrote:
**
This is all perfectly reasonable so far. When you create the JVM you'll
need to tell it where jess.jar is, along with any other jars you use, with
the -cp flag or the java.class.path property.
Once you have this working, you'll presumably want to connect things a
little more tightly. You can use the JNI API to write the equivalent of your
three-line main() in C++ pretty easily; you'll want to put together a C++
version executeCommand() that controls the Rete instance, passes a script
along, executes it, and gets the Value back, decoding it as needed.
--
*From:* owner-jess-us...@sandia.gov [mailto:owner-jess-us...@sandia.gov] *On
Behalf Of *Hunter McMillen
*Sent:* Monday, September 26, 2011 8:51 PM
*To:* jess-users
*Subject:* JESS: Call Jess from C++ via JNI
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));
System.out.println(v.intValue(r.getGlobalContext()));
}
}
But when I try to compile and link the C++ file with:
*cl *
* -IC:\Program Files\Java\jdk1.7.0\include *
* -IC:\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
*Questions*
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++?
Thanks,
Hunter McMillen
Re: JESS: Call Jess from C++ via JNI
Well the framework and API I am using are very large, so much so that it
would be unreasonable to rewrite them in Java. Sorry for the somewhat
unspecific question? Really I wanted to know why the class loader couldn't
find the jess.Rete class, when I have jess.jar on my classpath, and have it
in the directory where the c++ program executes.
Here is the c++ code where I create the JVM:
*#include jni.h*
*#include cstdlib*
*using namespace std;*
*int main() *
*{*
* JNIEnv *env;*
* JavaVM *jvm;*
* jint res;*
* jclass cls;*
* jmethodID mid;*
* jstring jstr;*
* jclass stringClass;*
* jobjectArray args;*
* *
* JavaVMInitArgs vm_args; /* JDK/JRE 6 VM initialization arguments */*
* JavaVMOption* options = new JavaVMOption[1];*
* options[0].optionString = (char*)-Djava.class.path=.; //the
current directory is where jess.jar is also*
* vm_args.version = JNI_VERSION_1_6;*
* vm_args.nOptions = 1;*
* vm_args.options = options;*
* vm_args.ignoreUnrecognized = false;*
*
*
* /* load and initialize a Java VM, return a JNI interface*
* * pointer in env */*
* JNI_CreateJavaVM(jvm, (void**)env, vm_args);*
* cls = env-FindClass(TestJNIJessInvoke);*
* mid= env-GetStaticMethodID(cls, main, **
([Ljava/lang/String;)V);*
* jstr = env-NewStringUTF();*
* stringClass = env-FindClass(java/lang/String);*
* args = env-NewObjectArray(1, stringClass, jstr);*
*
*
* env-CallStaticVoidMethod(cls, mid, args);*
* *
* if (env-ExceptionOccurred()) *
* {*
* env-ExceptionDescribe();*
* }*
* jvm-DestroyJavaVM();*
*}*
On Tue, Sep 27, 2011 at 11:58 AM, Dusan Sormaz sor...@ohio.edu wrote:
Hunter,
This is not Jess specific question. JVM simply can not find Java class to
load.
Can you show snippet of the C++ code that starts jvm and tries to load
TestJNIJessinvoke?
As for overall design, is C++ requirement? Can you do it all in Java?
Dusan Sormaz
On 9/26/2011 8:51 PM, Hunter McMillen wrote:
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));
System.out.println(v.intValue(r.getGlobalContext()));
}
}
But when I try to compile and link the C++ file with:
*cl *
* -IC:\Program Files\Java\jdk1.7.0\include *
* -IC:\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
*Questions*
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
RE: JESS: Call Jess from C++ via JNI
The problem is here. The Java classpath doesn't list directories in which jar files can be found, but rather, the jar files themselves. The argument should be, e.g., -Djava.class.path=./jess.jar. options[0].optionString = (char*)-Djava.class.path=.; //the current directory is where jess.jar is also
