java调用c++的几种方式

package crayon.jni;  
  
public class JNITest {  
    public native static void set(int i);  
    public native static int get();  
    static{  
        System.loadLibrary("JNITest");  
    }  
      
}  

#ifdef JNATEST_EXPORTS  
#define JNATEST_API __declspec(dllexport)  
#else  
#define JNATEST_API __declspec(dllimport)  
#endif  
  
extern "C" {  
    JNATEST_API void set(long l);  
    JNATEST_API long get();  
}  
#include "stdafx.h"  
#include "JNATest.h"  
  
long tmp;  
JNATEST_API void set(long l){  
    tmp = l;  
}  
JNATEST_API long get(){  
    return tmp;  
}  

import com.sun.jna.Library;  
import com.sun.jna.Native;  
  
public interface JNATest extends Library {  
    JNATest INSTANCE = (JNATest) Native.loadLibrary(  
                "D:/CC/Tools_Tool_ITT_StdPrj_Dev/PF_Tools_VOB/Tools_SubTool/src/JNATest/Release/JNATest", JNATest.class);  
    public void set(int i);  
    public int get();  
  
}