[che-dev] Support for multiple Java versions

[tmader@xxxxxxxxxx]

Hi folks,

we're trying to fix https://github.com/eclipse/che/issues/13547 and in have multiple ways to attack this problem:

1. We go back to basing our tooling on Java 8. 

Some support for modern features (modules, etc.) may be missing in the IDE.

2. We have multiple plugins for Java support in Che 7 

This would mean having plugins with id redhat/java8, redhat/java11. Existing workspaces and devfiles would have to be updated

3. Include multiple JDK's in the sidecar

Devfiles could override the jdk that is used through setting the JAVA_HOME env var. The user can override this in the preferences (java.home pref) The downside to this is that the tooling sidecar grows by 250M for every version we include

Our current thinking is that we would not support all versions, but only Java 8 and Java 11.

I'd be interested in hearing some feedback what the best way forward would be.

thx, Thomas