Unigraphics CPP JNI Memory Access violation.

Question

I have written a CPP code to get datas from Unigraphics which internally calls java through jni. I have created a dll using vc++6.0.
when i run the dll from Unigraphics I am getting this problem.
Prob: memory access violation.
But i can able to create JVM using
res = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);
But when i use cls = env->FindClass("Prog");
i am getting this error from Unigraphics.
(Note : CPP code can be invoked only from Unigraphics. b'cos Its a internal call from unigraphics through dll. This works fine when i write external cpp code to retrive datas from Unigraphics with jni code).
If needed vl send the code.

Answer 1

thanks for your reply.
Most of the examples I have found on the net use a 3 parameter call to getStringUTFchars looking something similar to this:
const char *str = GetStringUTFChars( env, some_jstring, 0);However when I try and add a third param in my dll file using VC++, i get a compile error saying:
error C2660: 'JNIEnv_::GetStringUTFChars' : function does not take 3 argumentseven though clearly in the stacktrace output I previously included, in one of the lines it says that JINEnv does take 3 params:
at JNIEnv_.GetStringUTFChars(JNIEnv_* , _jstring* str, Byte* isCopy)I am not sure why but using 2 params is the only way i can get the dll to compile correctly.
That is why I used      const char *cName;
     const char *wName;
     cName = env->GetStringUTFChars( className,false);
     wName = env->GetStringUTFChars( windowName, false);Also, as I said at the end of my first post, somehow the program worked a few times ( 3-4 ) without giving me the errors, and thus, gave me the intended output. However, I have not been able to get it to work since then, nor do I know what I did, or what happened so that it would work in the first place.
-Dale
Message was edited by:
smithdale87