You need to include the Java class name and path in your native code, for example if your native method was declared in Java as:
public class NativeCode {
public static native boolean CreateSession();
}
and the class path was (for example) com.example.NativeCode
you would declare your method in native as follows:
extern "C"
JNIEXPORT jboolean JNICALL Java_com_example_NativeCode_CreateSession(JniEnv* env, jclass clazz)
{
return JNI_TRUE;
}
All JNI methods have a JNIEnv pointer and class as their first two parameters.