What version of Java should I use with Cassandra 2

Question

Cassandra 2.0.12 and Datastax Enterprise 4.6 both recommend using Oracle Java SE 7. However, public updates of Java SE 7 will cease in April 2015 meaning security updates and bug fixes will not be available without a support contract with Oracle.

My preferred option would be OpenJDK to avoid legal hassles with Oracle's click-through license (technically I can avoid the problem, but legally I cannot). However, it seems that OpenJDK is not recommended for 'reasons'. I can only see minor reasons why it doesn't work (using the string 'icedtea' in the version string) and no recent discussions, so I'm assuming it is not being tested and should be avoided.

Should I be doing new deployments with Oracle Java SE 8, OpenJDK 7, OpenJDK 8, or some other variant?

Answer 1

I would recommend using the version DataStax recommends if you can. While other JDK variants and versions will likely work, it would make sense to use what QA is actively testing with and others in the community are using. Cassandra even goes so far to warn you if you are using OpenJDK or a non-Oracle JVM (code).

You should be able to get away with using OpenJDK 7, but just beware that you may encounter various problems with heap, load, kernel errors, etc. With regards to Java8, Cassandra 2.0 won't compile on Java 8 (CASSANDRA-7028), but you should be able to run with it.