implementation group: 'commons-cli', name: 'commons-cli', version: '1.4'

CommandLineParser parser = new DefaultParser();

Options options = new Options();
options.addOption("a", "all", false, "do not hide entries starting with .");
options.addOption("A", "almost-all", false, "do not list implied . and ..");
options.addOption(Option.builder()
                  .longOpt("block-size")
                  .desc("use SIZE-byte blocks")
                  .hasArg()
                  .argName("SIZE")
                  .build());

if (args.length == 0) {
    HelpFormatter formatter = new HelpFormatter();
    formatter.printHelp("ls", options);
    return;
}

try {
    CommandLine line = parser.parse(options, args);
    if(line.hasOption( "block-size" )) {
        System.out.println("block-size: " + line.getOptionValue("block-size"));
    }
    if (line.hasOption("a")) System.out.println("a");
    if (line.hasOption("A")) System.out.println("A");
} catch (ParseException e) {
    System.out.println( "Unexpected exception:" + e.getMessage() );
}

System.getProperty("user.dir")