如何使用JNA在Java代码中使用dll文件？

Question

I have to use a dll file (of c code) in my java code, for which I searched allot and found that JNA is the most suitable way for it. Therefore, I am trying to write a HelloWorld program using jna-4.1.0.jar. Below is the c code:

//C hello world example
#include <stdio.h>

void __declspec(dllexport) _stdcall helloFromC()
{
  printf("Hello world from the c code! \n");
}

and I make dll for this c code by using the following commands on cmd:

gcc -c ctest.c
gcc -shared -0 test.dll ctest.o

running these commands gives me a dll for the c code, which I place at the root of my simple java project.

Now here is my java class:

import com.sun.jna.Native;
import com.sun.jna.Library;

public class HelloWorld {

public interface CTest extends Library {
    void helloFromC();
}

 public static void main(String[] args) {
        CTest INSTANCE = (CTest) Native.loadLibrary("ctest", CTest.class);

        INSTANCE.helloFromC();
    }
}

Now when I run this java program on eclipse, I am getting this error:

Exception in thread "main" java.lang.UnsatisfiedLinkError: %1 is not a valid Win32 application.

Kindly help me to solve this issue as it has already taken much of time!

Answer 1

gcc -c ctest.c
gcc -shared -o test.dll ctest.o
try     'o'  ^  not '0'

It's finding your dll but it doesn't like it.