Re: [9] RFR (XS): 8169000: Define reference reachability more precisely in java.lang.ref package

[Zoltán Majó]

Hi David,

On 11/14/2016 11:52 PM, David Holmes wrote:
[...]

I don't think you need the "(i.e ...)". You are cross referencing to 
the Reachability section where "strongly reachable" is defined.

I see. OK, I've removed the "i.e.,".


The fewer the changes the better - the key part is to make it clearer 
that it "may" never be enqueued, without getting bogged down with why, 
or why not.

I agree.


Of course this will need to go through CCC.

Thank you for letting me know. I'll take care of the CCC approval once 
we have a changeset that we all agree upon.

Please see the updated webrev in my reply to Mandy.

Best regards,


Zoltan


Thanks,
David


Does that look reasonable to you?

Thank you!

Best regards,


Zoltan


The following modified test shows this situation:


public class WeaklyReachablePhantomReference {

    static ReferenceQueue<Object> rq = new ReferenceQueue<>();
    static WeakReference<PhantomReference<Object>> weakRefRef;

    public static void main(final String[] args) throws Exception {
        weakRefRef = new WeakReference<>(
            new PhantomReference<>(
                new Object(),
                rq
            )
        );
        // <- here
        System.gc();
        Reference rmRef = rq.remove(1000);
        if (rmRef == null) {
            System.out.println("PhantomReference NOT enqueued");
        } else {
            System.out.println("PhantomReference enqueued");
        }
    }
}


At "<-- here" the PhantomReference object becomes weakly reachable
while its referent becomes phantom reachable and this is enough for
PhantomReference to not be enqueued.


Regards, Peter