Sending commands to server via JSch shell channel

Question

I can\'t figure it out how I can send commands via JSch shell channel.

I do this, but it doesn\'t work:

JSch shell = new JSch();
String command = \"c         


        

Answer 1

try this code :

         JSch jsch=new JSch();

         System.out.println("Getting session");
         Session session=jsch.getSession("root","10.0.0.0",22);

          System.out.println("session is ::::"+session.getHost());
          // username and password will be given via UserInfo interface.
          UserInfo ui = new MyUserInfo("Lab@123", null);
          //UserInfo ui = new MyUserInfo(password, null);
          session.setUserInfo(ui);
          session.setPassword("Lab@123");
          Properties config = new java.util.Properties();
          config.put("StrictHostKeyChecking", "no");
          session.setConfig(config);
          session.connect(40000);


              Channel channel=session.openChannel("exec"); 
              ((ChannelExec)channel).setCommand("ls");

              channel.connect();
              channel.run();

              // get I/O streams for remote scp
              OutputStream out=channel.getOutputStream();
              InputStream in=channel.getInputStream(); 


          String output="";
          while (channel.isClosed()!=true) {

              try {
                output+=streamToString(in);

            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }

            System.out.println("Output is :::"+output);
            channel.disconnect();
            session.disconnect();
    }

    public static String streamToString(InputStream input)throws Exception 
    { String output = ""; while(input.available()>0) { output += ((char)(input.read())); } return output; }



    public static OutputStream stringToStream(String charset) throws IOException{

        byte[] bytes = charset.getBytes();
        /*ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
        InputStreamReader isr = new InputStreamReader(bais);*/
        InputStream is = null;
        OutputStream os = null;
        try {
            is = new ByteArrayInputStream(charset.getBytes("UTF-8"));
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        //byte[] buf = new byte[1024];
        int numRead;

          while ( (numRead = is.read(bytes) ) >= 0) {
              os.write(bytes, 0, numRead);
          }        
        return os;      

Answer 2

With piped input and output streams seems interesting:

JSch jsch = new JSch();
jsch.addIdentity("/home/audrius/.ssh/blablabla", "blablablabla");

String user = "audrius";
String host = "ultrastudio.org";

Session session = jsch.getSession(user, host, 439);
session.setConfig("StrictHostKeyChecking", "no");           
session.connect();

Channel channel = session.openChannel("shell");

PipedInputStream pip = new PipedInputStream(40);
channel.setInputStream(pip);

PipedOutputStream pop = new PipedOutputStream(pip);
PrintStream print = new PrintStream(pop);           
channel.setOutputStream(System.out);

print.println("ls");

Answer 3

I realize that this is an old thread, but I have struggled with a similar problem today. This is my solution.

public class ChannelConsole {

// ================================================
// static fields
// ================================================

// ================================================
// instance fields
// ================================================

private Session session;

// ================================================
// constructors
// ================================================

public ChannelConsole(Session session) {
    this.session = session;
}

// ================================================
// getters and setters
// ================================================

// ================================================
// public methods
// ================================================

public String execute(String command) throws JSchException {
    command = command.trim() + "\n";

    ChannelExec channel = (ChannelExec) this.session.openChannel("exec");
    channel.setCommand(command);

    ByteArrayOutputStream responseStream = new ByteArrayOutputStream();
    channel.setOutputStream(responseStream);

    channel.connect();

    try {
        awaitChannelClosure(channel);
    } catch (InterruptedException e) {
        // no one cares
    }

    String result = responseStream.toString();
    closeQuietly(responseStream);
    return result;

}

// ================================================
// private methods
// ================================================

private void awaitChannelClosure(ChannelExec channel) throws InterruptedException {
    while (channel.isConnected()) {
        Thread.sleep(100);
    }
}

private static void closeQuietly(Closeable closeable) {
    if (closeable == null) {
        return;
    }

    try {
        closeable.close();
    } catch (IOException ignored) {
        ignored.printStackTrace();
    }
}

}

Using this class you can just do something like : shell = new ChannelConsole(this.session); String result = shell.execute("quota -v; echo; echo \"Disk storage information:\"; df -hk")