Dryuf CmdLine

Command line structure

Support for building command line applications, including hierarchical with subcommands.

$ ./target/homecontrol --help
Usage: homecontrol options... command...

Options:
--id homeId    id of home, according to your list of homes you own or control

Commands:
help [command]       Prints help or help of subcommand
door arguments...    Controls door
sell                 Sells the home

$ ./target/homecontrol --id my door --door front open
Door open: front

The source code:

public class HomeControlCommand extends AbstractParentCommand
{
	private static final Map<String, Class<? extends Command>> COMMANDS = ImmutableMap.of(
			"help", HelpOfHelpCommand.class,
			"door", DoorCommand.class,
			"sell", SellCommand.class
	);

	private Options options;

	/**
	 * Entry point.
	 *
	 * @param args
	 * 	program arguments
	 *
	 * @throws Exception
	 * 	in case of error.
	 */
	public static void main(String[] args) throws Exception
	{
		AppContext appContext = new CommonAppContext(Guice.createInjector(new GuiceBeanFactoryModule()).getInstance(BeanFactory.class));
		System.exit(new HomeControlCommand().run(
				new RootCommandContext(appContext).createChild(null, "homecontrol", null),
				Arrays.asList(args)
		));
	}

	@Override
	protected void createOptions(CommandContext context)
	{
		this.options = new Options();
	}

	@Override
	protected Map<String, String> configOptionsDescription(CommandContext context)
	{
		return ImmutableMap.of(
				"--id homeId", "id of home, according to your list of homes you own or control"
		);
	}

	@Override
	protected Map<String, String> configCommandsDescription(CommandContext context)
	{
		return ImmutableMap.of(
				"help [command]", "Prints help or help of subcommand",
				"door arguments...", "Controls door",
				"sell", "Sells the home"
		);
	}

	@Override
	protected Map<String, Class<? extends Command>> configSubCommands(CommandContext context)
	{
		return COMMANDS;
	}

	@Override
	protected CommandContext createChildContext(CommandContext commandContext, String name, boolean isHelp)
	{
		return commandContext.createChild(this, name, Collections.singletonMap(Options.class, options));
	}

	@Override
	protected boolean parseOption(CommandContext context, String arg, ListIterator<String> args) throws Exception
	{
		switch (arg) {
		case "--id":
			options.id = needArgsParam(options.id, args);
			return true;

		default:
			return super.parseOption(context, arg, args);
		}
	}

	@Override
	protected int validateOptions(CommandContext context, ListIterator<String> args) throws Exception
	{
		if (options.id == null) {
			return usage(context, "Option --id not specified");
		}
		return EXIT_CONTINUE;
	}

	public static class Options
	{
		String id;
	}
}

The classes are created automatically by bean container and are being injected their properties as declared in their relevant modules.

License

The code is released under version 2.0 of the Apache License.

Stay in Touch

Zbynek Vyskovsky

Feel free to contact me at [email protected] and http://github.com/kvr000