Drop Java 8 Support

[hcoles]

Pitest will finally be dropping support for Java 8 this year and switching to Java 11 as a minimum version.

This issue is an opportunity for teams using pitest to discuss any problems this plan might cause. Please do not use it to advocate for instead raising the minimum to 17/21 etc.

Java 8 bytecode will still be supported for mutation, but a jvm of 11 or higher will be required to run pitest.

[balayanv]

Isn't java 8 still the most used JDK version? I remember until very recently stats were showing that 8 is still the most popular even though JVM used to run code was much more up-to-date people still kept using 8.

[hcoles]

I think the new relic report had java 8 usage now below that of java 11. But the question is, what versions of Java are the teams using pitest deploying on? If may be skewed in either direction.

[bitPogo]

May I ask, if you factored the Android into this decision?

[hcoles]

@bitPogo I'm not an android developer, so perhaps don't understand the impact. Can you elaborate?

[hcoles]

This link seems to suggest recent android versions require Java 11 or higher

https://developer.android.com/build/jdks#compileSdk