在Windows启动时由C ++应用程序启动JAR文件将无法运行

Question

I have a JAR file, which I want to run on system startup (OS=Windows). To achieve the program to be run on system start, I've done two things:

• I made an executable in C++, which will trigger the JAR file to be started.
• Created a registry key named MyApp (name doesn't actually matter) in HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Windows/CurrentVersion/Run with as value the path to the executable.

The code of the executable is as follows:

BOOL WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR commandLine, int nCmdShow) {

    ShowWindow(GetConsoleWindow(), SW_HIDE);

    // First display a box with text 'Hello!'
    stringstream msg; msg << "Hello!";
    MessageBox(NULL, msg.str().c_str(), "", MB_OK);

    // getJavaHome is a function
    stringstream javadir; javadir << getJavaHome() << "\\bin\\java.exe";
    stringstream params; params << " -jar jarfile.jar";

    STARTUPINFO info = { sizeof (info) };
    PROCESS_INFORMATION processInfo;

    char* path = stringToCharArray(javadir.str().c_str());
    char* args = stringToCharArray(params.str().c_str());

    if (CreateProcess(path, args, NULL, NULL, TRUE, CREATE_NO_WINDOW, NULL, NULL, &info, &processInfo)) {
        ::WaitForSingleObject(processInfo.hProcess, INFINITE);
        CloseHandle(processInfo.hProcess);
        CloseHandle(processInfo.hThread);
    }
    return 0;
}

Notice that, as you can see, this program will, before starting the JAR file, output a message box saying "Hello!"

Now here's the strange thing:

• When I run the executable by double-clicking on it, it will display the messagebox and then it'll start the JAR file.
• But when the system starts up and the application is triggered to be started, it will display Hello , but it won't start the JAR file.

How on earth come? Annnd... How to solve it?

Answer 1

I suppose it's a problem with the working directory—eventually it is completely different when autostarted. So you should either pass the proper working directory (can't tell if this can be done with CreateProcess() ); or give a fixed absolute path to your JAR file.