How to execute linux command “dzdo su - john” thro

2019-05-30 15:45发布

问题:

I want to connect to the remote linux server using java jsch library and switch to another user using command dzdo su - john and I want to execute some commands on that user. I have tried several ways on this requirement but I am unable to do this could any one help on this.

 public static void main(String args[])
    {
    String host="xxxxx.yyyy.com";
    String user="user";
    String password="password";
    String command1="dzdo su - lucy";
    try{    
        java.util.Properties config = new java.util.Properties(); 
        config.put("StrictHostKeyChecking", "no");
        JSch jsch = new JSch();
        Session session=jsch.getSession(user, host, 22);
        session.setPassword(password);
        session.setConfig(config);
        session.connect();
        System.out.println("Connected");

        Channel channel=session.openChannel("shell");
        OutputStream ops = channel.getOutputStream();
        PrintStream ps = new PrintStream(ops, true);

         channel.connect();
         ps.println(command1);
         ps.println("ls -ltr");
        InputStream in=channel.getInputStream();
        byte[] tmp=new byte[1024];
        while(true){
          while(in.available()>0){
            int i=in.read(tmp, 0, 1024);
            if(i<0)break;
            System.out.print(new String(tmp, 0, i));
          }
          if(channel.isClosed()){
            System.out.println("exit-status: "+channel.getExitStatus());
            break;
          }
          try{Thread.sleep(1000);}catch(Exception ee){}
        }
        channel.disconnect();
        session.disconnect();
        System.out.println("DONE");
    }catch(Exception e){
        e.printStackTrace();
    }
}

    }

by executing this code I am getting an output like this and the program is not halting

 Connected
Last login: Thu Oct  4 13:24:38 2018 from xx.xx.xxx.xx

    $  dzdo su - lucy
    xxxx@zr1.xxxx.com:/u/zr1.xxxx.com/lucy $ 

the command ls -ltr was not executing. The program was going to infinite loop in the statement while(true){---code---}

回答1:

It might be a timing issue.

Consider adding Thread.sleep between the two println calls.

ps.println(command1);
Thread.sleep(1000);
ps.println("ls -ltr");

Or try disabling PTY:

((ChannelShell)channel).setPty(false);
channel.connect();

If that works, it's a more robust solution than the delay.