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A licensing change means that although Oracle's JDK releases are still available for free use by developers, they are no longer free for production use.
Note that this situation has again changed as of Java 17, for which Oracle have introduced a new free Java license.
The Oracle JDK and OpenJDK code bases have come much closer together, such that we no longer anticipate large functional differences between the two.
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We anticipate that Red Hat's "vendor" OpenJDK (both OpenJDK 8 and OpenJDK 11) distribution for their own Red Hat Enterprise Linux will be used by many of our deployers simply because of the convenience factor. We therefore support the use of Red Hat's OpenJDK release distributions in this context.
We do not support Red Hat's OpenJDK releases for Windows at this time, and we do not test against them.
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OpenJDK 8 is supported by Red Hat on supported underlying RHEL distributions (currently, RHEL 7+) until May 2026.
OpenJDK 11 is supported by Red Hat on supported underlying RHEL distributions (currently, RHEL 7+) until October 2024.
OpenJDK 17 is supported by Red Hat on supported underlying RHEL distributions (currently, RHEL 8.5+) until October 2027.
Debian OpenJDK
Debian 9, also known as "stretch", the “oldoldstable” release at 2021-08-23, ships a vendor-supplied OpenJDK 8 only. This is partially supported for the Java 7 platform and IdP v3, but is obviously ineligible for any support for the Java 11 platform and IdP v4.
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