Fix Java version selection

[jacek-lewandowski]

Problem: for Cassandra 5 not built from the sources, Java version is not selected properly - it is assumed it works with either current version or Java 8.

Fixes:

• For Cassandra 5.1+ binary distribution, the supported versions are retrieved from cassandra.in.sh
• If supported Cassandra version cannot be retrieved from either build.xml (source dist) or cassandra.in.sh (bin dist), use the hardcoded version - the conditions cover all supported Cassandra versions starting from 2.2.
• Refactored Java selection logic - clearly distinguish supported Java versions by Cassandra and available Java versions in the environment (distributions configured via JAVA_HOME and JAVAn_HOME env variables); prioritizes the supported Java version over the current Java version configured via PATH (which is currently needed for upgrade testing)
• More explanatory messages about the Java version selection
• Added --jvm-version command line option for explicitly setting Java version with cluster or node start commands
• Fixed Cassandra version used to resolve Java version for running node tool (it was using Cassandra version defined for the cluster instead of the node which might have been upgraded)

[michaelsembwever]

lgtm, aside from one comment.

this needs to be tested thoroughly with all the different dtest test types (especially the upgrade variants), on all CI systems (as we filter out how we select jdks differently on each).

[michaelsembwever]

Thinking more about this…

if path_jvm_version in supported_versions
  use path_jvm_version
if java_home_jvm_version in supported_versions
  use java_home_jvm_version
else
  find JAVA[supported version]_HOME env variable and use that version if env variable found

Wouldn't it be a much simpler PR if we just put in an assert that PATH is correct according to JAVA_HOME ?

What do we gain from adding the complexity that we can honour either PATH or JAVA_HOME ?

[jacek-lewandowski]

The dtest branch for verification: https://github.com/jacek-lewandowski/cassandra-dtest/commit/13ac8ac168ffb78c26a11d389bda4c3085fba02a

The cassandra branch for verification: https://github.com/jacek-lewandowski/cassandra/commit/0356018e00e41d13147e345b362f269e934b2d14 in CircleCI

Jenkins tests are running at http://34.88.161.37:8080/blue/organizations/jenkins/cassandra/detail/cassandra/63/pipeline

[jacek-lewandowski]

https://app.circleci.com/pipelines/github/jacek-lewandowski/cassandra/1354/workflows/82c94bfc-3095-416e-b494-cb956a8989e0/jobs/72770

[jacek-lewandowski]

http://34.88.161.37:8080/blue/organizations/jenkins/cassandra/detail/cassandra/65/pipeline/

[michaelsembwever]

http://34.88.161.37:8080/blue/organizations/jenkins/cassandra/detail/cassandra/65/pipeline/

this isn't a permanent or accessible-to-all url. it's result files are in ccm_pull_766_65_ci.zip

[michaelsembwever]

+1