Title: Java 11 Support for Spark Overlay Author: Yuan Liao Posted: 2022-01-22 Revision: 1 News-Item-Format: 2.0 As Gentoo will soon start to support selecting JDK 11 as the system VM on stable keywords, all Java packages in ::spark-overlay have been updated so they can now be built using JDK 11. Users can now elect to use packages in this overlay with Java 11. New users of this overlay should note that as of 2022-01-22, a few Java packages in ::gentoo that are depended by packages in this overlay have JDK 11 build failure bugs, so they must be built with JDK 8: - dev-java/eclipse-ecj:4.5 [1] - dev-java/rxtx [2] All other Java packages provided or needed by this overlay can be built with JDK 11. Packages already installed on the system that were built by JDK 8 should continue to work on JRE 11. If any runtime error occurs after switching from JRE 8 to JRE 11, please first perform a @world update to make sure packages from both ::gentoo and ::spark-overlay are all up-to-date, as some package updates include fixes for Java 11 issues. If the problem persists, please try to rebuild packages from this overlay with JDK 11, using the following procedure: 1. Use 'eselect java-vm' to ensure that JDK 11 is selected as the system VM. Instructions are available on Gentoo Wiki [3]. 2. Install package app-portage/spark-overlay-rebuild, and run command 'spark-overlay-rebuild' to start rebuilding packages in this overlay. Before building any Java packages in this overlay with JDK 11, please be aware that some of the packages are known to have backward compatibility issues with Java 8 if they were built using JDK 11. If those packages have already been built with JDK 11 and need to be used on Java 8, they must be rebuilt using JDK 8. This overlay provides another package app-portage/java-11to8-rebuild that can be used to rebuild them without rebuilding the entire set of Java packages from this overlay. For more information, please see the related discussion thread [4]. Please feel free to use the discussion board [5] for any questions, suggestions and comments. Bugs related to packages in this overlay may be reported to the issue tracker [6]. [1]: https://bugs.gentoo.org/831084 [2]: https://bugs.gentoo.org/831394 [3]: https://wiki.gentoo.org/wiki/Java#Configuring_the_Java_Virtual_Machine [4]: https://github.com/Leo3418/spark-overlay/discussions/1 [5]: https://github.com/Leo3418/spark-overlay/discussions [6]: https://github.com/6-6-6/spark-overlay/issues