[DEBUG] java中用Runtime调用python 简单程序输出null

@Test

	public void testRuntime() throws InterruptedException {

        Scanner input = new Scanner(System.in);

        // 在同一行输入两个数字，用空格分开，作为传入Python代码的命令行参数

        System.out.println("Enter two integers(e.g. 12 34): ");

        String integers = input.nextLine();

        String[] numbers = integers.split(" ");

        // 定义传入Python脚本的命令行参数，将参数放入字符串数组里

        String cmds = String.format("python F:\\eclipse\\springboot2\\demo\\src\\test\\java\\com\\example\\demo\\cal.py %s %s", numbers[0], numbers[1]);

        // 执行CMD命令

        System.out.println("\nExecuting python script file now.");

        Process pcs;

		try {

			pcs = Runtime.getRuntime().exec(cmds);

			pcs.waitFor();

	        // 定义Python脚本的返回值

	        String result = null;

	        // 获取CMD的返回流

	        BufferedInputStream in = new BufferedInputStream(pcs.getInputStream());

	        // 字符流转换字节流

	        BufferedReader br = new BufferedReader(new InputStreamReader(in));

	        // 这里也可以输出文本日志

	        String lineStr = null;

	        while ((lineStr = br.readLine()) != null) {

	            result = lineStr;

	        }

	        // 关闭输入流

	        br.close();

	        in.close();

	        System.out.println(result);

		} catch (IOException e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

	}

#coding=utf-8

from sys import argv

num1 = argv[1]

num2 = argv[2]

sum = int(num1) + int(num2)

print sum

print(sum)