Trying to execute shell process in Linux

Question

Hi. I'm trying to execute a simple command in the form of 'bash -c "ls ~root ~"' from within java. I've tried using both the java.lang.Runtime.exec() methods and the java.lang.ProcessBuilder class but both produce the same error message (which I get from the OutputStream of the Process):
bash: ls ~root ~: command not found
A command such as 'bash -c "ls"' succeeds, providing the contents of my home directory in the Process's InputStream that I can display from within the program, but one in which there are one or more arguments to 'ls' fails the same way as above.
It seems that when I have a 'bash -c "ls <arguments>" as the command from within java, bash believes that the entire argument in double quotes ("ls <arguments>") is the command. It doesn't seem to "see" the spaces.
Would anyone know what I might do in this case? Below is my code:
import java.util.ArrayList;
import java.io.*;
public class ShellCommand {
    public static void main(String args[]) {
        ArrayList<String> shellCommandLine = new ArrayList<String>(3);
        shellCommandLine.add("bash");
        shellCommandLine.add("-c");
        shellCommandLine.add("\"ls ~root ~\"");
        InputStream is = null;
        ProcessBuilder pb = new ProcessBuilder(shellCommandLine);
        pb.redirectErrorStream(true);
        try {
            Process p = pb.start();
            is = p.getInputStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(is));
            String line;
            while ((line = br.readLine()) != null) {
                System.out.println(line);
            br.close();
        } catch (IOException ie) {
            System.out.println("Error executing external process.\n");
            System.exit(1);
}

Answer 1

I have just used Runtime.exec() on        final String[] command = {"bash","-c", "ls ~root ~" };As expected, the stderr stream produces
ls: /root: Permission denied
and stdout produces a directory listing of ~ (my home directory).
You should read the man page for bash -c and read http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html to see how to handle stdout and stderr.