Eclipse Scout 9.0 is now being tested against OpenJDK 11.
The Eclipse Scout 9.0 runtime components currently do still work using a Oracle JDK 8 runtime, however, due to the licencing changes by Oracle and End-of-Life of Java 8, we no longer test this and cannot guarantee compatibility going forward.
RedHat OpenJDK
Due to only a restricted set of elliptic curves being available in RedHat's build of OpenJDK 11, Scout 9.0 does not work out-of-the-box with it. For more information and workaround, see the Java 11 section of the release notes.