code: private static CommandLine parseCommandLine(final String[] vsArgs) {
          try {
              Group opts = configureCommandLine();
              // configure a HelpFormatter
              HelpFormatter hf = new HelpFormatter();
  
              // configure a parser
              Parser p = new Parser();
              p.setGroup(opts);
              p.setHelpFormatter(hf);
              // p.setHelpTrigger("--help");
              return p.parse(vsArgs);
          } catch (OptionException oe) {
              printUsage(oe);
          } catch (Exception e) {
              e.printStackTrace();
              // Should never happen...
          }
          return null;
      }
docs: Parses the command line.
  
  @param vsArgs
  The command line
  @return The parsed command line