在java程序中使用c ++ dll [英] use c++ Dll in java program

问题描述

我试图使用 System.LoadLibrary（）使用在c ++中写的简单dll。

UseDllInJava.java：

  import com.sun.jna.Library; 
 import com.sun.jna.Native; 
 import com.sun.jna.NativeLong; 
 import com.sun.jna.Platform; 
 import com.sun.jna。*; 
 
 / ** 
 *创建者Amit Baz on 06/06/2016。 
 * / 
 public class UseDllInJava {
 
 
 static {
 System.loadLibrary（SimpleDll）; 
} 
 public native static void HelloFromCPP（）; 
 
 public static void main（String [] args）{
 
 
 HelloFromCPP（）; 
} 
 
} 
  

这是dll： p>

SimpleDll.h

  #pragma once 
 $ b b namespace SimpleDll 
 {
 class MyFunctions 
 {
 public：
 static __declspec（dllexport）void HelloFromCPP（）; 
 
}; 
} 
  

SimpleDll.cpp：

  #includeSimpleDll.h
 #include< stdio.h> 
 #include< iostream> 
 
 using namespace std; 
 
命名空间SimpleDll {
 externC{
 void MyFunctions :: HelloFromCPP（）{
 cout< Hello from cpp<< endl; 
} 
} 
} 
  

我还添加了变量

-Djava.library.path =Path\To\ SimpleDll到Intellij运行配置中的VM选项。

但是当我运行程序时，它返回错误：

线程main中的异常java.lang.UnsatisfiedLinkError：
UseDllInJava.HelloFromCPP（）V

我得到了帮助。

从本教程： https://www3.ntu.edu.sg /home/ehchua/programming/java/JavaNativeInterface.html

此外，我不知道JNI命名约定是 Java_< ; Package_name> _< Class_name> _< Function_name>

解决方案 http://stackoverflow.com/questions/6092200/how-to-fix-an-unsatisfiedlinkerror-cant-find-dependent-libraries-in-a-jni-pro\">如何修复UnsatisfiedLinkError（找不到依赖库）在一个JNI项目，他们也讨论 java.lang.UnsatisfiedLinkError

I'm trying to use the System.LoadLibrary() to use a simple dll i wrote in c++.

UseDllInJava.java:

import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.NativeLong;
import com.sun.jna.Platform;
import com.sun.jna.*;

/**
 * Created by Amit Baz on 06/06/2016.
 */
public class UseDllInJava {


    static{
        System.loadLibrary("SimpleDll");
    }
    public native static void  HelloFromCPP();

    public static void main(String[] args){


        HelloFromCPP();
    }

}

This is the dll:

SimpleDll.h

#pragma once

namespace SimpleDll
{
    class MyFunctions
    {
    public:
        static __declspec(dllexport) void HelloFromCPP();

    };
}

SimpleDll.cpp:

#include "SimpleDll.h"
#include <stdio.h>
#include <iostream>

using namespace std;

namespace SimpleDll {
    extern "C" {
        void MyFunctions::HelloFromCPP() {
            cout << "Hello from cpp" << endl;
        }
    }
}

I also added the variable

-Djava.library.path="Path\To\SimpleDll" to the VM options in the Intellij run configurations.

But when I run the program it returns the error:

Exception in thread "main" java.lang.UnsatisfiedLinkError: UseDllInJava.HelloFromCPP()V

EDIT

Now it works!

I got help from this tutorial: https://www3.ntu.edu.sg/home/ehchua/programming/java/JavaNativeInterface.html

Also I didn't know that the JNI naming convention is Java_<Package_name>_<Class_name>_<Function_name>

解决方案

Check this thread How to fix an UnsatisfiedLinkError (Can't find dependent libraries) in a JNI project they are also discussing java.lang.UnsatisfiedLinkError

这篇关于在java程序中使用c ++ dll的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！