Following the recent announcement of the candidate JEP on sealed types (preview), Gavin Bierman's message "Draft JLS spec for sealed types" on the OpenJDK amber-spec-experts mailing list announces "a draft language spec for sealed types" and provides a link to that draft. That message also states: "This spec doesn't yet contain details on binary compatibility (Chapter 13) — to appear in the next draft."
You may also like: Candidate JEPs: Records and Sealed Types
In this post, I highlight some of the proposed changes to the Java Language Specification (JLS) for sealed types. It is important to keep in mind the tentativeness of these proposed changes: this is an of JLS changes for a feature associated with a JDK Enhancement Proposal (JEP).