RFR: 8275338: Add JFR events for notable serialization situations [v5]

[Roger Riggs]

On Wed, 20 Dec 2023 14:28:39 GMT, Roger Riggs <rriggs at openjdk.org> wrote:

>> Raffaello Giulietti has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Changes according to reviewer's comments.
>
> It would also be useful/interesting to include a test that checks every Serializable class (by  Invoking `ObjectStreamClass.lookup(clazz)`) in the Java runtime and reports any jfr events.  
> Fixing them would be a separate task.  The compiler warnings from last year should have fixed most/many non-conforming classes.

> @RogerRiggs Do you mean a permanent test in the codebase, or just a throwaway run? Anyway, interesting suggestion.

A separate PR to add permanent test would advise about the current state and prevent new cases.
If there are cases that can't be fixed (because of some kind of backward compatibility issue), there might need to be an exclusion list.

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PR Comment: https://git.openjdk.org/jdk/pull/17129#issuecomment-1864639166