RFR: 8283417: Update java.nio buffers to use sealed classes

[Alan Bateman]

On Tue, 22 Mar 2022 17:02:45 GMT, Brian Burkhalter <bpb at openjdk.org> wrote:

> Seal subclassed buffer classes and make non-subclassed buffer classes final.

This change looks okay and has no real impact as buffer classes cannot be extended from code outside of the java.nio runtime package. An advantage of making the hierarchy sealed is that it will show up in the javadoc and that might those that show up periodically asking about extending these classes.

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Marked as reviewed by alanb (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/7907