Set Java Object with Java Long Object from JNI

Question

Hi,
i am getting crazy with the jni...
in Java i have the follwoing:
public class blabla{
Object myObject;
i chose Object cause the return value from native is not known
in case for a long value i handle it like this :
//get the Long class
jclass LongCls = env->FindClass("Ljava/lang/Long;");
jmethodID jmid = env->GetMethodID(LongCls, "<init>","(J)V");
//create an Long Object with the long return value
jobject LongObj = env->NewObject(LongCls,jmid,longreturnvalue);
//set Long Objekt - doesnt work!(jclazz is the class of the return Object of the blabla class)
jfid = env->GetFieldID(jclazz, "myObject", "Ljava/lang/Object;");
env->SetObjectField( returnobjectofblabla,jfid,LongObj );
the long value is set fine in the Long Object but i cant set the Long Object with the SetObjectField method into the Object myObject.
Java is shown that the myObject contains a Long Object but the long value of the Long Object is totally wrong and doesnt equal to the long value which has been set.But setting the value works fine- any ideas or solutions?
Thank you!

Answer 1

charliess wrote:
sometimes i really wonder about the answers in this forum - until now i got not one answer that helps me, even i tried to write down the problem very detailed...
Sometimes I wonder about people who jump onto a site and immediately assume that
1. They are the most important person in the world
2. That they deserved the absolute undivided attention of absolute everyone.
3. That everyone should be absolutely polite to them and provide them with perfect answers.
4. Feel free to denigrate and posit their own opinion on everything while ignoring anything else that anyone else says.
5. Expect that everyone else should understand their poorly worded questions.
Myself I find such individuals extremely amusing. Although they seldom stick around long here. At least not under their original alias.
plaz tel me how to realise your error checking?example plz
You start by having at least a basic understanding of C/C++ and java.
Then you read the JNI documents, all of them, for each method that you are using.
Then you write code such that it actually reflects the documents. For example you check return types. And probably deal with the possibility that JNI methods might throw exceptions.
as far as i know the jni methods like getfieldids and so on throw exceptions other like stObject dont do that the just return nothing
i can see all exceptions in my Java console thats not the Problem, setting the Long Object does not throwing a exception btw->
Myself I wouldn't expect that a JNI exception would show in the java console. Could I suppose though.
However nothing so far would suggest that an exception is being thrown. That however doesn't alter the fact that you must still write the code such that it could happen.
is it possible in general to set an java Long Object created in C(native) into a Object type (Object) overgiven as parameter in my JNI function with the setObject method?
Is it possible that you could actually follow my previous request and create some code that actually runs instead of cut and pasting whatever you feel like?
plz answer also with code and examples i did the same for you...No you didn't. You posted something which would not compile and quite possibly doesn't represent your actual code at all.
And please note that we do not get paid to do this. If you want to pay someone to solve your problem then there are sites for that.
Paying someone allows you to make all sorts of demands. The more you pay the more people will put up with.
If you don't want to pay and do in fact want free answers then it will probably be in your interest to
1. Be polite
2. Answer the questions that have been asked of you.