We have 2 SonarQube instances running one with 7.9 and other 8.4 and we have projects (Maven and Gradle) using Java 8 and Java 11.
Is there any dependency that projects should also use java 11 for them to work with 8.x versions? or projects can be analysed without any issues with them still using java 8?
For now, analysis still works with Java 8. That will be changing "soon"TM, so it’s probably best to go ahead and upgrade.
That said, it’s worth noting that you can build with Java 1.4 (E.G.) and you’re still golden as long as you analyze with the currently required version (currently Java 8).