<dependency> <groupId>com.martiansoftware</groupId> <artifactId>jsap</artifactId> <version>2.1</version> </dependency> import com.martiansoftware.jsap.*; public class CommandLineParser { public static void main(String[] args) throws JSAPException { SimpleJSAP jsap = new SimpleJSAP("MyProgram", "A simple program using JSAP for command line arguments."); FlaggedOption inputOption = new FlaggedOption("input") .setStringParser(JSAP.STRING_PARSER) .setDefault("default_input.txt") .setRequired(true) .setShortFlag('i') .setLongFlag("input"); jsap.registerParameter(inputOption); JSAPResult arguments = jsap.parse(args); if (!arguments.success()) { System.err.println("Error parsing command line arguments: " + arguments.getErrorMessage()); System.err.println("Usage: " + jsap.getUsage()); System.exit(1); } String input = arguments.getString("input"); System.out.println("Input file: " + input); } }