Java 9 introduced the Java Platform Module System. The introduction of the module system affects existing applications and offers new ways of creating modular and maintainable applications. With this hands-on book, Java developers will learn not only about the joys of modularity, but also about the patterns needed to create truly modular and reliable applications. Authors Sander Mak and Paul Bakker teach you the concepts behind the Java Platform Module System, along with the powerful tools it offers. You'll also learn how to modularize existing code and how to build new Java applications in a modular way.