The next cheat sheet includes:
Test-Driven development
Stream Pipelines.
equals().
equals()
hashCode() (for next challenge).
hashCode()
HashMap (for next challenge).
HashMap
static and final.
static
final
Naming conventions.
https://www.learnthepart.com/course/2dfda34d-6bbc-4bd5-8f45-d5999de2f514/eab9f27c-c3ae-4542-a15a-407e33526d61