RFR: 8207851 JEP Draft: Support ByteBuffer mapped over non-volatile memory

[Chris Hegarty]

Hi Andrew,

> On 15 Feb 2019, at 16:51, Andrew Dinn <adinn at redhat.com> wrote:
> 
> The latest round of changes to the JEP and draft implementation are now
> available for review:
> 
> JEP:    http://openjdk.java.net/jeps/8207851
> webrev: http://cr.openjdk.java.net/~adinn/pmem/webrev.05/


I'm only following this issue at a high-level, but I have one suggestion
that I think would help clarify the scope of this feature.

If I understand the changes correctly, then the feature is actually
accessed through the JDK-specific ExtendedMapMode READ_ONLY_SYNC and
READ_WRITE_SYNC map modes. This kinda implies that the JEP should be
scoped at the JDK level ( rather than Java SE ).

I see that there are changes to the Java SE Platform, namely to the
MapMode constructor and an overload of MappedByteBuffer::force. I see
these more as "enablers" in support of this feature ( rather than the
core of the feature itself ). They can happen as part of the same
changeset, or could possibly be pushed separately upfront.

If you agree, then the only action needed is to change the `Scope` of
the JEP from `SE` to `JDK`.

-Chris.