Exception change? and Reason?

[Lee Rhodes]

In Java 21 FFM, attempting a write operation on a MemorySegment configured
as ReadOnly throws a *UnsupportedOperationException (UOE),* which makes
sense.

However, starting with Java 22, FFM, attempting a write operation on a
MemorySegment configured as ReadOnly throws a *IllegalArgumentException
(IAE),* which makes less sense to me.

I guess you could argue it either way, but one could look at it this way:

   - The target is correct, but the operation is incorrect -- thus, UOE
   makes sense
   - The target of the operation is incorrect, but the operation is correct
   -- thus, IAE makes sense
   - The target is correct and the operation is correct, but the target is
   incorrectly configured as read-only -- thus UOE makes sense
   - Both the target and the operation are incorrect -- thus, either UOE or
   IAE could make sense.

Of these 4 cases, I would think the first 3 are the most common, in which
case the UOE would be the most likely cause.

I'm sure the Java authors must have a more eloquent reason why this was
changed, and I tried to find release notes that would explain this change
but to no avail.

Please enlighten me.

Lee.
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