Background
There's been some discussion in several ICT meetings to move forward to Java 11 and OpenJDK, both for possible licensing issues and to avoid obsolescence and lack of support. During last ICT Leads Meeting in Socorro 2018, it was finally decided that the upgrading effort would be made aiming for Cycle 8 and that a Go/NoGo decision would be made somewhere between July and September. During the latest discussions it was decided to go with July 26th as the Go/NoGo decision date.
Current Status
During COMMON-2019APR the core changes required in ACS were implemented:
COMMON-2019JUN was more focused in fixing compilation and execution issues that were found out as other subsystems started they're porting efforts:
Good Practices
ACS and COMMON in general has been generating delivery branches from master, skipping the creation of pull requests to avoid any mix-up of merges when the releases have been verified and merged back to master, as the date to merge Java 11 related changes is different from the usual delivery cycle, to avoid breaking up any previous release changes.
There's a long lived branch integration/java11 that is being used to merge all changes related to Java11. It is recommended to merge only from delivery branches and to avoid direct commits there, to avoid any work being lost at the end of the Java 11 merging procedure (1).
We've made sure to align integration/java11 to master and also to the current COMMON branch in progress. At this point integration/java11 has all the changes from integration/COMMON-2019JUN.