The Java Champions conference at the end of January featured the Java Champions presenting various topics within the Java ecosystem. All videos are available and you should definitely check them out if you missed them.
If you are interested in security I recommend the OWASP Top Ten talk by Jim Manico who goes through the most popular application vulnerabilities and what developers can do about it.
There is a great tool I also would like to mention: ASDF, a polyglot runtime system able to support various languages and version (i.e. Node 14, 16 and 17, Python 3.3, 3.6, etc..). If you are working with multiple languages it makes your life a lot easier as you can easily switch to a different runtime (called plugins) and specific version. Give it a go and share your experience with us.