Switch off Args4j Command Line Processing

[romeara]

Args4j, based on this issue, appears to be abandoned.

The recommended upgrade path appears to be a library called picocli, with these resources:

• https://picocli.info/
• https://github.com/remkop/picocli
• https://devops.datenkollektiv.de/an-introduction-to-picocli.html

In addition, some multi-command stuff:

• What to do for multiple commands remkop/picocli#518
• https://github.com/remkop/picocli/blob/master/picocli-examples/src/main/java/picocli/examples/subcommands/ParentCommandDemo.java

[romeara]

The Maven coordinate for the library is info.picocli:picocli. An example of a multi-command app could be:

public class CommandLineInterface {

    public static void main(String[] args) throws Exception {
        new CommandLine(new ContainerCommand())
                .addSubcommand(new FirstCommand())
                .execute(args);
    }

    @Command(mixinStandardHelpOptions = true)
    public static class ContainerCommand implements Runnable {

        @Override
        public void run() {
            // Empty, this just creates a reasonable command setup - this is the equivalent to something like "git" in git commands
        }

    }

    @Command(description = "...", name = "method-uses", mixinStandardHelpOptions = true)
    public static class FirstCommand implements Callable<Void> {

        @ParentCommand
        private ContainerCommand containerCommand;

        @Option(names = { "--source", "-s" }, description = "source dir", required = true)
        private String directory;

        @Option(names = { "--output", "-o" }, description = "File to output results to", required = false)
        private String outputFile;

        @Override
        public Void call() throws Exception {
            // Do stuff
        }
    }

}