I recently gave a presentation to my Keyhole team members about JUnit 5. I started off the presentation by covering the importance of automated testing, how lack of automated testing affects an organization’s ability to deliver code to production, and how without automated testing you are building legacy.

I pointed out two key benefits of automated testing: confidence you are fixing what you set out to fix, and confidence you are not introducing a new bug. A co-worker however pointed out an important third benefit of automated testing: providing living documentation.

My co-worker made the very good point that automated testing can do more than just checking for code correctness. It can also provide valuable documentation for current and future developers on a project.

In this article, we look at how using AssertJ can make automated tests easier to read and write. We take a look at how AssertJ improves the readability of assertions in test cases, as well as how it helps make the task of comparing complex objects and performing list validations easier to read and write. The goal is that when tests are easier to read and write, it will hopefully encourage developers to write more tests (i.e. documentation).