Backport of JEP 254 (Compact Strings) to OpenJDK 8

[Aleksey Shipilev]

On 01/12/2017 08:11 PM, John Platts wrote:
> I am interested in OpenJDK 8 builds with JEP 254 (Compact Strings) support
> backported from OpenJDK 9. I like the compact strings work that is being done
> in JDK 9, but I am interested in a OpenJDK 8 build with backported JEP 254
> support since I am working with Java applications that might not work in
> OpenJDK 9 yet and since I would like take advantage of the feature in a
> backported OpenJDK 8 build instead of having to wait for the JDK 9 release.

This was discussed a number of times both internally and externally, and the
maintainers' consensus was that the feature is too intrusive VM- and JDK- wise.
Backporting it would be very painful, and probably destabilizing for JDK 8.

Think about the work one does enabling applications to run on JDK 9 as the price
to get Compact Strings :)

Thanks,
-Aleksey