public static ShutdownArgs parse(final String[] args) {
        try {
            CommandLineParser parser = new DefaultParser();
            CommandLine cmd = parser.parse(createShutdownOptions(), args);
            return new ShutdownArgs(StartArgsParser.getPort(cmd.getOptionValue("s")));
        } catch (ParseException e) {
            throw new ParseArgException("fail to parse arguments", e);
        }
    }
@Test
    public void should_parse_shutdown_default_arguments() {
        ShutdownArgs args = parse(new String[]{"shutdown"});
        assertThat(args.getShutdownPort().isPresent(), is(false));
    }