如题，现在有一个第三方的dll文件“Mwic_32.dll”，由于是第三方的，必须要用JNI实现，我的具体步骤如下：
先在java中定义一个类：
- Java code
public class AAA { static { System.load("C:/AUTO_INIT.dll"); } public native static int auto_init(int a,int b); public static void main(String args[]){ AAA new_auto_init = new AAA(); System.out.println("Result="+new_auto_init.auto_init(0, 38400)); }}之后用javah AAA生成头文件AAA.h
在DEV C++中新建一个dll工程，名字为“AUTO_INIT”
之后复制AAA.h中的内容到AUTO_INIT.h的最前边
最后实现AUTO_INIT.cpp中的方法Java_AAA_auto_1init（调用Mwic_32.dll中的auto_init函数）
并生成AUTO_INIT.dll
其中，AUTO_INIT.h代码如下：
- C/C++ code
/* DO NOT EDIT THIS FILE - it is machine generated */#include "jni.h"/* Header for class AAA */#ifndef _Included_AAA#define _Included_AAA#ifdef __cplusplusextern "C" {#endif/* * Class: AAA * Method: auto_init * Signature: (II)I */JNIEXPORT jint JNICALL Java_AAA_auto_1init (JNIEnv *, jclass, jint, jint);#ifdef __cplusplus}#endif#endif///////////////////////////////////////////////////////#ifndef _DLL_H_#define _DLL_H_#if BUILDING_DLL# define DLLIMPORT __declspec (dllexport)#else /* Not BUILDING_DLL */# define DLLIMPORT __declspec (dllimport)#endif /* Not BUILDING_DLL */class DLLIMPORT DllClass{ public: DllClass(); virtual ~DllClass(void); private:};#endif /* _DLL_H_ */AUTO_INIT.cpp代码：
- C/C++ code
/* Replace "dll.h" with the name of your header */#include<windows.h>#include<stdio.h>#include "AUTO_INIT.h"#include <windows.h>JNIEXPORT jint JNICALL Java_AAA_auto_1init (JNIEnv * nev, jclass obj, jint a, jint b){ //const int * aa=a; //const int * bb=evn->GetInt(b); //void * objptr = CreateAUTO_INIT(); HINSTANCE hdll = NULL; hdll = LoadLibrary ( "Mwic_32.dll" ); typedef BOOL ( _stdcall *lpFileEncrypt )( INT, INT); lpFileEncrypt FileEncrypt1; FileEncrypt1 = ( lpFileEncrypt )::GetProcAddress( hdll, "auto_init" );//调用dll中的函数 int result = FileEncrypt1(0,38400); FreeLibrary( hdll ); //printf("restult=%d",result); //int result=auto_init(a,b); //env->ReleaseInt(a,aa); //env->ReleaseInt(b,bb); return result; }DllClass::DllClass(){}DllClass::~DllClass (){}BOOL APIENTRY DllMain (HINSTANCE hInst /* Library instance handle. */ , DWORD reason /* Reason this function is being called. */ , LPVOID reserved /* Not used. */ ){ switch (reason) { case DLL_PROCESS_ATTACH: break; case DLL_PROCESS_DETACH: break; case DLL_THREAD_ATTACH: break; case DLL_THREAD_DETACH: break; } /* Returns TRUE on success, FALSE on failure */ return TRUE;}最后我把生成出来的AUTO_INIT.dll文件放在C盘下，但是用java运行是确提示“An unexpected error has been detected by Java Runtime Environment:”
具体的出错信息如下：
#
# An unexpected error has been detected by Java Runtime Environment:
#
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00000000, pid=3644, tid=3696
#
# Java VM: Java HotSpot(TM) Client VM (11.0-b16 mixed mode, sharing windows-x86)
# Problematic frame:
# C 0x00000000
#
# An error report file with more information is saved as:
# C:\app1\AAA\hs_err_pid3644.log
#
# If you would like to submit a bug report, please visit: