I'm not quite sure what you are talking about. Maybe you mix up JNI and
serialization?

What is your problem? What do you want to do? What happens instead?

Even if it is hard in your case, a short, consistent example would
be much appreciated.

Why? If you merely want to wrap some preexisting C routines (as you said
you wanted) your library should never have to know about java objects.

There is no good way. Java Objects and C structs are apples and
oranges. They may look similar from a distance, but are totally
incompatible. (Of course, you can obtain a pointer to the data
that constitutes a java object, but what good would it do you? You
only get references in JNI anyway)

Example for this is :

JAVA Layer :
public class MyInteger implements java.io.Serializable
{
 public int value;
}

Calling this function in Java file as :
MyInteger obj = new MyInteger();
obj.value = 10;
inVoidStar(obj);

JNI Layer, Now I want to pass jobject to in_void_star() C functions?
Same thing for the values which comes as out value from C to Java as
VOID**?

JNIEXPORT void JNICALL Java_1impl_inVoidStar(JNIEnv *env, jobject
_pObject, jobject void_obj)
{
    /*
    jclass cls = env->GetObjectClass(void_obj);
    jfieldID fid = env->GetFieldID(cls,"value", "I");
       int value = env->GetIntField(void_obj, fid);
       void *void_ptr = &value;
    */
          int API_status = in_void_star((void*)void_obj);
} // inVoidStar

C Layer :
extern int in_void_star(void* ptr)
{
       int *p = (int*)ptr;
    printf("in_void_star() : %d\n", *p);
    return 0;
}

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