Urgent!! PB write a program in C/C++ who start a JVM and invoke a method ja

Question

I try to write a program in C/C++ who start a JVM and invoke a method java.
my program run fine if in my essai method, i do't call the JNI method ierror().
but when i call the ierror() there's a bug :
enter in essai
Exception in thread "Thread-0" java.lang.AbstractMethodError
at prog.Prog.client(Prog.java:12)
what's wrong???
Thanks for your help.
// Prog.java
package prog;
import testnative.jAppEngine;
public class Prog extends jAppEngine
     public void main (String[] args)
     public void essai();
          System.out.println("enter in essai");
          ierror();
          System.out.println("quit essai");
// jAppEngine.java
public class jAppEngine
     public native void ierror();
     static
          System.loadLibrary("jEngine");
// jEngine.cpp (my jEngine.dll)
* Class: testnative_jAppEngine
* Method: ierror
* Signature: ()V
JNIEXPORT void JNICALL Java_testnative_jAppEngine_ierror
(JNIEnv *env, jobject jobj) )
     ierror( "Dans jAppEngine.ierror");
// Application.cpp
JavaVM *vm = 0;
int startJVM( )
char *s = 0;
int ret;
jboolean jvmspecified = JNI_FALSE; /* Assume no option specified. */
char jrepath[MAXPATHLEN], jvmpath[MAXPATHLEN];
int i, knownVMsCount;
/* If we got here, jvmpath has been correctly initialized. */
ifn.CreateJavaVM = 0;
ifn.GetDefaultJavaVMInitArgs = 0;
if (!LoadJavaVM(jvmpath, &ifn))
     return 6;
/* Set default CLASSPATH */
if ((s = getenv("CLASSPATH")) == 0)
          s = ".";
SetClassPath(s);
/* Initialize the virtual machine */
if (!InitializeJVM(&vm, &env, &ifn))
     fprintf(stderr, "Could not create the Java virtual machine.\n");
ret = 1;
return ret;
int LaunchClass( char classname, char jentry, void *p )
int retval;
jclass mainClass;
jmethodID mainID;
JNIEnv *env;
retval = vm->AttachCurrentThread((void **)&env,NULL);
jcls = LoadClass(env, classname);
/* Get the application's main method */
mainID = env->GetMethodID( mainClass, jentry, "()V");
/* Invoke main method. */
env->CallVoidMethod( mainClass, mainID); //, mainArgs);
if ((*vm).DetachCurrentThread() != 0)
     fprintf(stderr, "Could not detach main thread.\n");
return ret;
static void th1(void *p)
     LaunchClass( "prog.Prog", "client", NULL);
     _endthread();
int main(int argc, char* argv[])
     startJVM();
     Beep(6000,500);
     for (int i=0; i<1; i++)
          _beginthread(&th1,0,&i);
          Sleep(500);
     return 0;
}

Answer 1

Hi! bschauwe
Thanks for reply.
My native method called ierror calls effectively a subroutine who's in another dll. I change the name of my native method, no effects always the same error message.
So, in my native method I replace ierror(...) by Beep(..) and it's the same.
I don't understand.