Java HotSpot Virtual Machine

New to JNI and having a nightmare trying to work this out. I've followed several tutorials but can't seem to get any of them to work in my circumstance.

I have a .dll file which has already been written and is called piapi32.dll. I'm trying to access the method piut_setservernode from this DLL file.

The code for my class is as below.

public class Main {
    /** Creates a new instance of JNITest */
    private native int piut_setservernode(String serverName);
    
    static {
        System.loadLibrary("piapi32");
    }    
    
    public Main() {
    }
    
    public static void main(String args[]) {
        try{
            Main jniTest = new Main();            
            
            int status = jniTest.piut_setservernode("ServerName");
        }catch(Exception ex){
            ex.printStackTrace();
        }
    }
}

I have then used javac and javah to compile the Main.h file which contains the below.

/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class Main */

#ifndef _Included_Main
#define _Included_Main
#ifdef __cplusplus
extern "C" {
#endif
/*
 * Class:     Main
 * Method:    piut_setservernode
 * Signature: (Ljava/lang/String;)I
 */
JNIEXPORT jint JNICALL Java_Main_piut_1setservernode
  (JNIEnv *, jobject, jstring);

#ifdef __cplusplus
}
#endif
#endif

I get an error "Exception in thread "main" java.lang.UnsatisfiedLinkError: piut_setservernode" on the line "int status = jniTest.piut_setservernode("ServerName");" when i run this program.

I've previously accessed this DLL from within Visual Basic using the below:

Declare Function piut_setservernode Lib "piapi32.dll" (ByVal servername$) As Long

Does anyone have any ideas of what i need to change or look at to get this working?

Regards

Jamie