For the past year and a half, we have been building and testing Derby
against early access versions of JDK 9. JDK 9 appears to be in the final
months of testing before GA. I have run the Derby regression tests
against Derby release 10.13.1.1, using the JDK 9 build 181 platform. The
tests run cleanly. My results are recorded at
https://issues.apache.org/jira/browse/DERBY-6856?focusedCommentId=16124749&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-16124749
In my opinion Derby is ready for JDK 9.
This is our last opportunity to provide feedback to the team which is
developing JDK 9. You are encourged to download the latest version of
JDK 9 from http://jdk.java.net/9/ and to test your Derby-powered apps on
that platform. Let me know if you discover any problems. I will forward
your feedback to the JDK team.
Thanks,
-Rick