Question

我正在尝试从java代码执行.py文件。我将.py文件移动到我的java项目的默认目录中，然后使用以下代码调用它：

    String cmd = "python/";
    String py = "file";
    String run = "python  " +cmd+ py + ".py";
    System.out.println(run);
    //Runtime.getRuntime().exec(run);

    Process p = Runtime.getRuntime().exec("python  file.py");

使用变量run，或整个路径或＆＃34; python file.py＆＃34;我的代码正在运行，显示消息构建成功总时间0秒而不执行file.py.我的问题在这里是什么？

Answer 1

您也可以这样使用：

String command = "python /c start python path\to\script\script.py";
Process p = Runtime.getRuntime().exec(command + param );

或

String prg = "import sys";
BufferedWriter out = new BufferedWriter(new FileWriter("path/a.py"));
out.write(prg);
out.close();
Process p = Runtime.getRuntime().exec("python path/a.py");
BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));
String ret = in.readLine();
System.out.println("value is : "+ret);

<强> Run Python script from Java

Answer 2

我相信我们可以使用ProcessBuilder

Runtime.getRuntime().exec("python "+cmd + py + ".py");
.....
since exec has its own process we can use that
ProcessBuilder builder = new ProcessBuilder("python", py + ".py");
builder.directory(new File(cmd));
builder.redirectError();
....
Process newProcess = builder.start();

Answer 3

String command = "cmd /c python <command to execute or script to run>";
    Process p = Runtime.getRuntime().exec(command);
    p.waitFor();
    BufferedReader bri = new BufferedReader(new InputStreamReader(p.getInputStream()));
    BufferedReader bre = new BufferedReader(new InputStreamReader(p.getErrorStream()));
          String line;
        while ((line = bri.readLine()) != null) {
            System.out.println(line);
          }
          bri.close();
          while ((line = bre.readLine()) != null) {
            System.out.println(line);
          }
          bre.close();
          p.waitFor();
          System.out.println("Done.");

    p.destroy();

Answer 4

您可以运行python脚本

Process p = Runtime.getRuntime().exec(PYTHON_ABSOLUTE_PATH, script_path)

要获得PYTHON_ABSOLUTE_PATH，只需输入

即可

which python2.7

在终端

Answer 5

尽管OP得到了答案，但我仍在发布解决方案，这可能会对像我这样的人有所帮助。

        File file = new File(("C:/.../file.py"));

        List<String> list = new ArrayList<String>();
        list.add("python.exe");
        String absPath = file.getAbsolutePath();

        System.out.println("absPath>>"+absPath);

        list.add(absPath);
        ProcessBuilder pb = new ProcessBuilder(list);
        Process process = pb.start();

        InputStream inputStream = process.getInputStream();
        byte[] b = new byte[1024 * 1024];// {(byte) 1024};
        while (inputStream.read(b) > 0) {
            System.out.println("b.length>>"+new String(b));
        }

        process.waitFor();
        System.out.println("exitValue()>>"+process.exitValue());    //Should return 0 on successful execution

从Java运行.py文件

5 个答案: