France-IOI system calls ?

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

class Main
{
    public static void main(String[] args)
    {
        Runtime r = Runtime.getRuntime();

        try
        {
            Process p = r.exec("ls -la");
            InputStream in = p.getInputStream();
            BufferedInputStream buf = new BufferedInputStream(in);
            InputStreamReader inread = new InputStreamReader(buf);
            BufferedReader bufferedreader = new BufferedReader(inread);

            // Read the ls output
            String line;
            while((line = bufferedreader.readLine()) != null)
            {
                System.out.println(line);
            }
            // Check for ls failure
            try
            {
                if(p.waitFor() != 0)
                {
                    System.err.println("exit value = " + p.exitValue());
                }
            }
            catch(InterruptedException e)
            {
                System.err.println(e);
            }
            finally
            {
                // Close the InputStream
                bufferedreader.close();
                inread.close();
                buf.close();
                in.close();
            }
        }
        catch(IOException e)
        {
            System.err.println(e.getMessage());
        }
    }
}