I want to execute [b]some shell [/b]commands in a java program

Question

Hello,
I would like to know if it's possible to execute some unix commands in the same "environment"... I mean, if I use the exec() function to execute the "cd /tmp" command, and after that, if I want to do "ls" , I'm not in the "/tmp" directory, know what I mean ??
In fact, I want to have in my GUI a textarea or something like that, in which one can enter several unix command like in a xterm window...
I don't know how to do that and if it's possible ??
Thank you very much for your answers !

Answer 1

OK !! It works with this code but I don't understand why I have to do "return" twice before the command execute ??
(I'm a newbie)
Here's the sample code:
import java.io.*;
public class Tonta {
private String dada="";
private BufferedReader in;
private InputStream instr;
private InputStream errstr;
private PrintStream outstr;
private Process transyt;
private Tonta t;
public Tonta() {
//Executem el programa
try {
transyt=Runtime.getRuntime().exec("ksh");
System.out.print("toto");
} catch (IOException e)
{System.out.println("EXCEPCION:exec"+ e.getMessage());}
instr= transyt.getInputStream();
errstr= transyt.getErrorStream();
outstr= new PrintStream(transyt.getOutputStream());
in = new BufferedReader( new InputStreamReader(System.in));
}//end of constructor
  public void run() {
    int exit=0;
    boolean processEnded= false;
    try {
      while (!processEnded) {
        try {
          exit = transyt.exitValue();
          processEnded = true;
        catch (IllegalThreadStateException e) {}
        System.out.print("\nREMOT:");
        System.out.flush();
        int n= instr.available();
        if (n>0) {
          byte[] pbytes= new byte[n];
          instr.read(pbytes);
          System.out.print(new String(pbytes));
          System.out.flush();
        n= errstr.available();
        if (n>0) {
          byte[] pbytes= new
          byte[n];
          errstr.read(pbytes);
          System.err.print(new
          String(pbytes));
          System.err.flush();
        System.out.println();
        System.out.print("LOCAL> ");
        System.out.flush();
        dada= in.readLine();
        if (dada.equals("exit")) {
          System.out.println();
          System.out.println("Programa finalizado");
          System.out.flush();
          transyt.destroy();
          instr.close();
          errstr.close();
          outstr.close();
          System.exit(0);
        outstr.println(dada);
        outstr.flush();
        try {
          Thread.sleep(10);
        catch (InterruptedException e) {}
      System.out.println();
      System.out.println("Process exited with:"+ exit);
      System.out.flush();
    } catch (IOException e) {
        System.err.println("EXCEPCION "+ e.getMessage());
public static void main (String [] args) {
Tonta t= new Tonta();
t.run();
}Thanks