cmdExec.java

/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
import com.jcraft.jsch.*;
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.util.Scanner;

public class cmdExec{
  public static void main(String[] arg){
    try{
      JSch jsch=new JSch();  

      String host=null;
      if(arg.length>0){
        host=arg[0];
      }
      else{
        System.out.println("Enter user@host:");
        Scanner scnUserHost = new Scanner(System.in);
        host = scnUserHost.nextLine();
      }
      String user=host.substring(0, host.indexOf('@'));
      host=host.substring(host.indexOf('@')+1);

      Session session=jsch.getSession(user, host, 22);

      System.out.println("Enter password:");
      Scanner scnUserPass = new Scanner(System.in);
      String paswrd = scnUserPass.nextLine();
      session.setPassword(paswrd);
      

      // username and password will be given via UserInfo interface.
      UserInfo ui=new MyUserInfo();
      session.setUserInfo(ui);
      session.connect();
      boolean keepGoing = true;
      while (keepGoing){
        Scanner cmdIn = new Scanner(System.in);
        System.out.println("Enter command");
        String command = cmdIn.nextLine();

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

        channel.setInputStream(null);

        ((ChannelExec)channel).setErrStream(System.err);

        InputStream in=channel.getInputStream();

        channel.connect();

        byte[] tmp=new byte[1024];
        while(true){
            while(in.available()>0){
              int i=in.read(tmp, 0, 1024);
              if(i<0)break;
              // grab the return, hopefully a number
              String strRet = new String(tmp, 0, i);
              // trim whitespace and convert to int
              int ret = Integer.parseInt(strRet.trim());
              System.out.print(ret);
            }
            if(channel.isClosed()){
              if(in.available()>0) continue;
              //System.out.println("exit-status: "+channel.getExitStatus());
              break;
            }
            try{Thread.sleep(1000);}catch(Exception ee){}
            
        }
        channel.disconnect();
        Scanner kgIn = new Scanner(System.in);
        System.out.println("Keep running commands? [y/n]");
        String kgStr = kgIn.nextLine();
        if (kgStr.equals("y") || kgStr == "y") {
          keepGoing = true;
        }
        else {
          keepGoing = false;
          session.disconnect();
        }
      }
    }
    catch(Exception e){
      System.out.println(e);
    }
  }

  public static class MyUserInfo implements UserInfo, UIKeyboardInteractive{
    public String getPassword(){ return passwd; }
    public boolean promptYesNo(String str){
      Object[] options={ "yes", "no" };
      int foo=JOptionPane.showOptionDialog(null, 
             str,
             "Warning", 
             JOptionPane.DEFAULT_OPTION, 
             JOptionPane.WARNING_MESSAGE,
             null, options, options[0]);
       return foo==0;
    }
  
    String passwd;
    JTextField passwordField=(JTextField)new JPasswordField(20);

    public String getPassphrase(){ return null; }
    public boolean promptPassphrase(String message){ return true; }
    public boolean promptPassword(String message){
      Object[] ob={passwordField}; 
      int result=
        JOptionPane.showConfirmDialog(null, ob, message,
                                      JOptionPane.OK_CANCEL_OPTION);
      if(result==JOptionPane.OK_OPTION){
        passwd=passwordField.getText();
        return true;
      }
      else{ 
        return false; 
      }
    }
    public void showMessage(String message){
      JOptionPane.showMessageDialog(null, message);
    }
    final GridBagConstraints gbc = 
      new GridBagConstraints(0,0,1,1,1,1,
                             GridBagConstraints.NORTHWEST,
                             GridBagConstraints.NONE,
                             new Insets(0,0,0,0),0,0);
    private Container panel;
    public String[] promptKeyboardInteractive(String destination,
                                              String name,
                                              String instruction,
                                              String[] prompt,
                                              boolean[] echo){
      panel = new JPanel();
      panel.setLayout(new GridBagLayout());

      gbc.weightx = 1.0;
      gbc.gridwidth = GridBagConstraints.REMAINDER;
      gbc.gridx = 0;
      panel.add(new JLabel(instruction), gbc);
      gbc.gridy++;

      gbc.gridwidth = GridBagConstraints.RELATIVE;

      JTextField[] texts=new JTextField[prompt.length];
      for(int i=0; i<prompt.length; i++){
        gbc.fill = GridBagConstraints.NONE;
        gbc.gridx = 0;
        gbc.weightx = 1;
        panel.add(new JLabel(prompt[i]),gbc);

        gbc.gridx = 1;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.weighty = 1;
        if(echo[i]){
          texts[i]=new JTextField(20);
        }
        else{
          texts[i]=new JPasswordField(20);
        }
        panel.add(texts[i], gbc);
        gbc.gridy++;
      }

      if(JOptionPane.showConfirmDialog(null, panel, 
                                       destination+": "+name,
                                       JOptionPane.OK_CANCEL_OPTION,
                                       JOptionPane.QUESTION_MESSAGE)
         ==JOptionPane.OK_OPTION){
        String[] response=new String[prompt.length];
        for(int i=0; i<prompt.length; i++){
          response[i]=texts[i].getText();
        }
	return response;
      }
      else{
        return null;  // cancel
      }
    }
  }
}