With that, our application is done. So, what have we covered? From the project description, this seemed like a pretty simple application, but as we started breaking down the requirements and delving into the implementation, we ended up covering a lot of territory--a scenario that is not at all uncommon. We built another multi-module Maven project. We introduced Java concurrency, including basic Thread management and ExecutorService usage, as well as the Java Persistence API, showing basic @Entity definition, EntityManagerFactory/EntityManager usage, and JPAQL query authoring. We discussed creating file hashes using the MessageDigest classes, and demonstrated the new file I/O APIs, including the directory tree walking APIs. We also built a more complex user interface in JavaFX using nested containers, "linked" ListView instances, and bound properties.
That's quite a bit for such a "simple" project. Our next project will also be relatively simple, as we build a command-line date calculator...