如何从java中调用C#函数
本文关键字:调用 函数 java | 更新日期: 2023-09-27 18:22:19
我需要从java调用C#函数,为此我创建了以下内容。我有一个创建java头文件Authenticator.h,这里是代码:
#include <jni.h>
/* Header for class Authenticator */
#ifndef _Included_Authenticator
#define _Included_Authenticator
#ifdef __cplusplus
extern "C" {
#endif
/*
* Class: Authenticator
* Method: authenticate
* Signature: (Ljava/lang/String;Ljava/lang/String;)Z
*/
JNIEXPORT jboolean JNICALL Java_Authenticator_authenticate
(JNIEnv *, jobject, jstring, jstring);
#ifdef __cplusplus
}
#endif
#endif
然后我创建了一个C#函数来验证
namespace SharpAuthenticator
{
public class Authenticator
{
public bool Authenticate(String username,String password)
{
return username == "user" && password == "login";
}
}
}
然后我尝试使用下面的代码从C++(创建dll的项目)调用C#函数;
String^ toString(const char *str)
{
int len = (int)strlen(str);
array<unsigned char>^ a = gcnew array<unsigned char>(len);
int i = 0;
while (i < len)
{
a[i] = str[i];
i++;
}
return Encoding::UTF8->GetString(a);
}
bool authenticate(const char *username, const char *password)
{
SharpAuthenticator::Authenticator::Authenticate(toString(username), toString(password));
}
JNIEXPORT jboolean JNICALL Java_Authenticator_authenticate
(JNIEnv *env, jobject c, jstring name, jstring pass)
{
jboolean result;
jboolean isCopyUsername;
const char * username = env->GetStringUTFChars(name, &isCopyUsername);
jboolean isCopypassword;
const char * password = env->GetStringUTFChars(pass, &isCopypassword);
result = authenticate(username, password);
env->ReleaseStringUTFChars(name, username);
env->ReleaseStringUTFChars(pass, password);
return result;
}
最后创建一个dll,我需要从java调用它。dll已经创建,我用java很好地加载了它,但我用java得到了这个错误日志。我会错过什么。
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (0xe0434352), pid=9708, tid=7756
#
# JRE version: 7.0-b147
# Java VM: Java HotSpot(TM) Client VM (21.0-b17 mixed mode, sharing windows-x86 )
# Problematic frame:
# C [KERNELBASE.dll+0x812f]
#
# Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
首先让我们创建一个C#文件,如下所示:
using System;
public class Test{
public Test(){}
public String ping(){
return "C# is here.";
}
}
然后用下面的命令编译:
csc.exe /target:module Test.cs
您可以在.NET框架的安装路径中找到csc.exe
。之后创建java文件:
public class Test{
public native String ping();
public static void main(String[] args){
System.load("/path/to/dll");
System.out.println("Java is running.");
Test t = new Test();
System.out.println("Trying to catch C# " + r.ping());
}
}
CCD_ 2这生成一个CCD_。
javah -jni Test
这将生成一个Test.h
文件,该文件将包含在C++代码。
之后,我们需要创建我们的C++文件:
#include "stdafx.h"
#include "JAVA/Test.h"
#include "MCPP/Test.h"
#pragma once
#using <mscorlib.dll>
#using "Test.netmodule"
JNIEXPORT jstring JNICALL Java_Test_ping(JNIEnv *env, jobject obj){
Test^ t = gcnew Test();
String^ ping = t->ping();
char* str = static_cast<char*>((System::Runtime::InteropServices::Marshal::StringToHGlobalAnsi(ping)).ToPointer());
char cap[128];
strcpy_s(cap, str);
return env->NewStringUTF(cap);
}
最后:
c:'>java Test
我希望这对你有帮助。在Java中使用函数C#的一个基本示例。
来源:https://www.quora.com/How-common-is-the-problem-of-calling-C-methods-from-Java-Do-many-developers-come-across-such-necessity