Why Java 21?
Free Long-Term Support (LTS) for OpenJDK 11 has reached end-of-life across all major distributions. This means security vulnerabilities in the Java runtime are no longer patched through regular update channels. Continuing to run Java 11 represents a growing security risk — regardless of whether you also update the Lobster Data Platform.
OpenJDK 21 is the current, compatible LTS release. It receives active security updates from all major distributions, including Adoptium and Eclipse Temurin. Starting with release 26.2, the Lobster Data Platform supports OpenJDK 21 as its primary runtime environment. We recommend aligning your upgrade plan with Java 21.
Schedule and Requirements
Platform version | Java requirement | Notes |
|---|---|---|
4.6.x, 25.x, 26.1 | OpenJDK 11 | No Java upgrade |
26.2 | OpenJDK 11 or OpenJDK 21 | As of release 26.2, OpenJDK 21 is the recommended runtime. OpenJDK 11 is still supported in 26.2 but has reached vendor end-of-life. |
Action required when upgrading to 26.2
Release 26.2 introduces two breaking changes that affect all on-premises installations — regardless of whether you are simultaneously migrating to Java 21:
The platform exclusively uses JDOM2 as of 26.2 (previously JDOM 1.x). Any custom code with
org.jdomimports must be migrated.JDBC driver compatibility must be verified — particularly for Microsoft SQL Server, which is a frequent source of issues.
Review the complete pre-upgrade checklist before proceeding.
Next Steps
Start with the checklist. It walks you through all required verification steps in the correct order: