java - 从 JAR 中执行 python 文件

Question

我想弄清楚如何引用 python 文件，以便我可以在 Java GUI Jar 中执行它。它需要是一个可移植的解决方案，所以使用绝对路径对我来说不起作用。我在下面列出了我的项目结构，并包含了我如何尝试执行 python 脚本的代码。我已经阅读了有关使用资源的内容，但我无法成功实现它。感谢您提供的任何帮助!

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    try {
        Runtime rt = Runtime.getRuntime();
        Process pr = rt.exec("python /scripts/script.py");

        BufferedReader bfr = new BufferedReader(new InputStreamReader(pr.getInputStream()));
        String line = "";
        while((line = bfr.readLine()) != null)
            System.out.println(line);
}
    catch(Exception e) {
        System.out.println(e.toString());
}
}   

--OneStopShop (Project)
  --Source Packages
    --images
    --onestopshop
      --Home.java
    --scripts
      --script.py

Answer 1

以 / 开头的文件路径意味着您希望从文件系统的根目录开始。

您的代码只需删除前导斜线即可为我工作:

public static void main(String[] args) {
    try {
        File python = new File("scripts/script.py");
        System.out.println(python.exists()); // true

        Runtime rt = Runtime.getRuntime();
        Process pr = rt.exec("python scripts/script.py"); // print('Hello!')

        BufferedReader bfr = new BufferedReader(new InputStreamReader(pr.getInputStream()));
        String line = "";
        while((line = bfr.readLine()) != null)
            System.out.println(line);
    }
    catch(Exception e) {
        System.out.println(e.toString());
    }
}

// true
// Hello!
// Process finished with exit code 0

之所以放错文件没有显示错误是因为这段java代码只显示输入流(getInputStream())，而不显示错误流(getErrorStream()):

    public static void main(String[] args) {
    try {
        Runtime rt = Runtime.getRuntime();
        Process pr = rt.exec("python scripts/doesnotexist.py");

        BufferedReader bfr = new BufferedReader(new InputStreamReader(pr.getErrorStream()));
        String line = "";
        while((line = bfr.readLine()) != null)
            System.out.println(line);
    }
    catch(Exception e) {
        System.out.println(e.toString());
    }
}

// python: can't open file 'scripts/doesnotexist.py': [Errno 2] No such file or directory
// Process finished with exit code 0