Is OpenJDK supported by Confluence?
Confluence 6.13 and later
We support running Confluence 6.13 and later with AdoptOpenJDK 8. AdoptOpenJDK is free to use, and provides regular maintenance and security updates. Paid support for AdoptOpenJDK is also available from organisations such as IBM.
Note that AdoptOpenJDK is the only OpenJDK vendor supported at this time. We also support running Confluence on Oracle JDK / JRE.
Confluence 6.12 and earlier
OpenJDK is not supported in Confluence 6.12 or earlier. A number of problems can occur when using OpenJDK, as Confluence's internal code as well as third party plugins assume you are using a supported JDK.