JDK 9 proposal: remove sun.misc.Ref

[Stuart Marks]

On 1/7/14 2:26 PM, Joe Darcy wrote:
>> public abstract class Ref {
>
> So the type has been deprecated for at least 10 years. Rather than fixing the
> warning in the class, I think the best course of action is to remove the file in
> JDK 9. A build of OpenJDK without this file builds fine; if a build of the
> closed sources goes fine to, I think that should be sufficient justification for
> this type to be removed.
>
> Using code search engines, there are just a handful of references to
> sun.misc.Ref in the wihld, but any such uses will have several years to migrate
> to the standard java.util.SoftReference before JDK 9 ships.

When in doubt, take it out.

I had a small concern about whether sun.misc.Ref still might have had some 
dependencies from the JVM (i.e. special support like the java.lang.ref classes), 
but it looks like sun.misc.Ref itself is entirely implemented in terms of 
java.lang.ref.SoftReference. I did a quick search of hotspot and I couldn't find 
any mentions of sun.misc.Ref, so I think we're clear.

s'marks