Jni Question Of Params

[mylaneza]

Hi all.
I'm working with JNI and I'am trying to wrap a .dll but i hava a question. This is my problem:

JAVA :

native void f(int x);

public static void main(String args){
int y = 8;
Object o = new Object();
o.f(y);
System.out.println(""+y);
}
C:

JNIEXPORT void JNICALL Java_Class_f (JNIEnv *env, jobject o, jint x){
//What do I have to put in here to make the x param will be modified
and the system shows 9 .
}

[JosAH]

Hi all.
I'm working with JNI and I'am trying to wrap a .dll but i hava a question. This is my problem:

JAVA :

native void f(int x);

public static void main(String args){
int y = 8;
Object o = new Object();
o.f(y);
System.out.println(""+y);
}
C:

JNIEXPORT void JNICALL Java_Class_f (JNIEnv *env, jobject o, jint x){
//What do I have to put in here to make the x param will be modified
and the system shows 9 .
}

You can't do that because Java uses the pass by value parameter passing mechanism.
You have to return the modified value from your native function or come up with
something else but what you want(ed) can not be done.

kind regards,

Jos

[mylaneza]

Thank you for your answer Jos