Airline

Airline is a Java library that makes it easy to build powerful command line applications. It supports both single commands, and multi-command git style CLIs. It is designed to minimise boilerplate code, being predominantly annotation driven, thus allowing developers to focus on application logic, not on how they parse their command line arguments.

I first encountered the original version of Airline in use in a competitors product around 2012, and quickly started experimenting with using it in my employers products as it provided such a nice command line user experience, and was much nicer for developers. However, there were some deficiencies which the original authors were not willing to accept PRs for as they had moved onto other projects. Therefore I forked this library and have been maintaining my own substantially enhanced fork since 2014.

An extensive user guide is available on the Airline website.

I've also previously run a workshop session on this - Building a Killer Command Line Application with Airline - that is also available on the project website.