Does Cassandra support Java 10?

Question

We\'re planning on migrating our environment from Java 8 to OpenJDK 10. Doing this on my local machine, I\'ve found that Cassandra will no longer start for me, giving the fo

Answer 1

Cassandra 4.0 has explicit support for both Java 8 and Java 11. In fact, they even split-up the configuration files as such:

$ pwd
/Users/aaron/local/apache-cassandra-4.0-SNAPSHOT/conf
$ ls -a jvm*
jvm-clients.options jvm11-clients.options   jvm8-clients.options
jvm-server.options  jvm11-server.options    jvm8-server.options

The reason for support of these specific versions is two-fold. First of all, Java 8 has been the de-facto standard for Cassandra for a few years now. Users expect that it will still work on Java 8 in the future.

Given the new 6 month release cycle of Java, Java 9 and Java 10 will no longer be "current" when Apache Cassandra 4.0 comes out. Plus, the tests which run during the build have shown to be picky about which version of Java they work with. Therefore, the decision was made to go support Java 8 and 11 for 4.0, as work on Java 9 and 10 seemed to be lower-priority.

That's not to say that Cassandra 4.0 won't run on Java 9 or 10. In fact, CASSANDRA-9608 even has a patch submitted which should cover it. But the fact remains that Java 8 is included due to its longstanding use in the Cassandra user base. Java 11 will be the current JDK/JRE at the time 4.0 releases. If you want to be sure that your cluster will run well, I'd pick one of those two.

But until 4.0, the most recent patch of Java 8 is really the only option.