I haven't read a Java manual since the time of Java 8. Do you have any books or other resources you could recommend to catch up with all that has changed in these years?
https://www.marcobehler.com/guides/a-guide-to-java-versions-...
https://advancedweb.hu/a-categorized-list-of-all-java-and-jv...
And this more like a reference:
- Functional Programming in Java
- Cruising Along With Java (this covers everything else that is "new" other than functional programming)