Command Prompt Shell Interface in Java

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Java

Windows

shell

I took a program that someone wrote for a terminal-like shell interface for UNIX. However, I would like to change this so it can emulate a command prompt, not a terminal.

The program compiles, but if I try, for example, running the simple command of "dir" within the program then it panics and exits. Something similar to this shows on exit:

CreateProcess error=2. The system cannot find the file specified.

The only command that runs successfully is the "help" command (and granted, the "exit" and "" commands.)

I would appreciate any help that could be given regarding the program below:

import java.io.*;
import java.util.*;

public class shell
{
    public static void main(String[] args) throws java.io.IOException {
        
        String commandLine;
        BufferedReader console = new BufferedReader
            (new InputStreamReader(System.in));
        
        while (true) {
            // read what the user entered
            System.out.print("My shell>");
            commandLine = console.readLine(); {
                // if the user entered a return, just loop again
                if (commandLine.equals("")) {
                    continue;
                }
                else if (commandLine.equalsIgnoreCase("exit")) {
                    System.out.println("Goodbye");
                    System.exit(0);
                }
                
                // split the string into a string array
                
                ArrayList<String> parms = new ArrayList<String>();
                String[] lineSplit = commandLine.split(" ");
                
                int size = lineSplit.length;
                for (int i=0; i<size; i++) {
                    parms.add(lineSplit[i]);
                }
                
                ProcessBuilder pb = new ProcessBuilder(parms);
                Process proc = pb.start();
                
                // obtain the input stream
                InputStream is = proc.getInputStream();
                InputStreamReader isr = new InputStreamReader(is);
                BufferedReader br = new BufferedReader(isr);
                
                // read what is returned by the command
                String line;
                while ((line = br.readLine()) != null)
                    System.out.println(line);
                    
                br.close();
                
            }
        }
    }
}