在进程终止之前从java进程获取stdInput

因此，我试图运行一个python脚本，并希望从脚本中获取stdInput，以便使用它。我注意到stdInput将一直挂起，直到进程完成

Python脚本：

import time
counter = 1
while True:
    print(f'{counter} hello')
    counter += 1
    time.sleep(1)

public class Main {

    public static void main(String[] args) throws IOException {
        Runtime rt = Runtime.getRuntime();
        String[] commands = {"python3", "/Users/nathanevans/Desktop/Education/Computing/Programming/Java/getting script output/src/python/main.py"};
        Process proc = rt.exec(commands);

        BufferedReader stdInput = new BufferedReader(new InputStreamReader(proc.getInputStream()));
        BufferedReader stdError = new BufferedReader(new InputStreamReader(proc.getErrorStream()));

        System.out.println("stdOuput of the command");
        String s = null;
        while ((s = stdInput.readLine()) != null) {
            System.out.println(s);
        }

        System.out.println("stdError of the command");
        while ((s = stdError.readLine()) != null) {
            System.out.println(s);
        }
    }
}

Java代码：

import time
counter = 1
while True:
    print(f'{counter} hello')
    counter += 1
    time.sleep(1)

public class Main {

    public static void main(String[] args) throws IOException {
        Runtime rt = Runtime.getRuntime();
        String[] commands = {"python3", "/Users/nathanevans/Desktop/Education/Computing/Programming/Java/getting script output/src/python/main.py"};
        Process proc = rt.exec(commands);

        BufferedReader stdInput = new BufferedReader(new InputStreamReader(proc.getInputStream()));
        BufferedReader stdError = new BufferedReader(new InputStreamReader(proc.getErrorStream()));

        System.out.println("stdOuput of the command");
        String s = null;
        while ((s = stdInput.readLine()) != null) {
            System.out.println(s);
        }

        System.out.println("stdError of the command");
        while ((s = stdError.readLine()) != null) {
            System.out.println(s);
        }
    }
}

在进程终止之前，java应用程序不会打印任何内容，但在本例中，当我终止java应用程序时

---

如何获得脚本编写的stdInput？

为了立即获得Python输出，您需要关闭Python输出缓冲，这已经介绍过了

这可能会解决您的问题，但您可能会遇到第二个问题，因为您正在一个线程中读取STD IN/OUT。如果在读取到STDIN结尾之前STDERR缓冲区已填充，则会阻止进程。然后，解决方案是在单独的线程中读取STD/IN/ERR，或者使用ProcessBuilder，它允许重定向到文件或将STDERR重定向到STDOUT：

ProcessBuilder pb = new ProcessBuilder(commands);
    pb.redirectOutput(outfile);
    pb.redirectError(errfile);
//or
    pb.redirectErrorStream(true);
Process p = pb.start();