从c ++运行jar文件 [英] run jar file from c++

问题描述

我运行下面的c ++代码，ret的值是-1（javavm的创建是falid）

I am runing the follwing c++ code and the value of "ret" is -1 (the create of javavm is falid)

代码的问题是什么？

#include <iostream>
#include <conio.h>
#include <jni.h>
using namespace std;
#pragma comment (lib,"jvm.lib");

int main(){
JavaVM *jvm;
JNIEnv *env;
JavaVMInitArgs vm_args;
JavaVMOption options;

options.optionString="hello.jar";
vm_args.version=JNI_VERSION_1_6;
vm_args.nOptions=1;
vm_args.Option=&options;
vm_args.ignoreUnrecognized=0;
int ret=JNI_CreatJavaVM(&jvm,(void**)&env,&vm_args);

 }

这是帮助

推荐答案

如果将 CreateJavaVM 调用中的无效选项传递给 ignoreUnrecognized = 1 它将无法启动JVM。

If you pass in an invalid option to the CreateJavaVM call, because of the ignoreUnrecognized = 1 it will fail to launch the JVM.

当我使用public static void main方法创建一个简单的jar时，下面的代码，它正确地调用了main方法：

When I create a simple jar with a public static void main method, and use the following code, it correctly invokes the main method:

JavaVM *jvm;
JNIEnv *env;
JavaVMInitArgs vm_args;
JavaVMOption options;
options.optionString = "-Djava.class.path=hello.jar";
vm_args.version = JNI_VERSION_1_6;
vm_args.nOptions = 1;
vm_args.options = &options;
vm_args.ignoreUnrecognized = 0;
int ret = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);
if (ret == 0) {
    jclass cls = env->FindClass("hello");
    if (cls != 0) {
        jmethodID meth = env->GetStaticMethodID(cls, "main", "([Ljava/lang/String;)V");
        jarray args = env->NewObjectArray(0, env->FindClass("java/lang/String"), 0);
        env->CallStaticVoidMethod(cls, meth, args);
    }
}
return ret;

这假设 hello.jar 可执行文件的工作目录。如果不是，则需要指定jar文件的完整路径。例如 c：\hello.jar 。

This assumes that hello.jar is in the working directory of the executable. If it isn't then you need to specify the full path to the jar file. e.g. c:\hello.jar.

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