Runtime.getruntime(cmd.exe C () Usage

The latest project was used to test the situation of the linuxlinuxsystem. A lot of data was found on the internet, and runtime.getruntime(cmd.exe C () was the most final method. I have never written a blog before. I learned to write a blog for the first time today.

First, run the correct code:

Khan, how can I paste the code? --

package com.fajun.shell.demo;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.util.ArrayList;import java.util.List;import java.util.Properties;public class DoShell { private static boolean getShellReturn(String shell_cmd,String shell_result) throws IOException{    Process process = Runtime.getRuntime().exec(shell_cmd);  InputStream inputStream = process.getInputStream();  InputStreamReader inputStreamReader = new InputStreamReader(inputStream);  BufferedReader bufferedReader = new BufferedReader(inputStreamReader);  List<String> strings = new ArrayList<String>();  String str = null;  while ((str = bufferedReader.readLine())!= null) {   strings.add(str);  }  for (int i = 0; i < strings.size(); i++) {   if (strings.get(i).contains(shell_result)) {    return true;   }  }    return false;  } private static  String getOSName(){    Properties properties = System.getProperties();  String os = properties.getProperty("os.name");  return os;  } public static void main(String[] args) {  String os = getOSName();  if (os.contains("inux")) {      String shell_cmd = "mount";   String shell_result="sda1";   boolean flag =false;   try {    flag = getShellReturn(shell_cmd, shell_result);   } catch (IOException e) {    e.printStackTrace();   }   System.out.println("the result is "+ flag);  }  System.out.println("os name is "+os);  }}

The above is a test code I wrote. Please refer to it for correction.

 

When I write this code, a problem occurs, that is, if the getshellresult () method is passed in for an exact search like "Mount | grep sda1, NO content can be found, but if you enter this command on the Linux console, it is a value. Why?