This proposes to update Reference::enqueue method to clear this reference object before enqueuing it to the registered queue consistent with what the garbage collector does that clears the reference object before putting it in the pending queue for enqueuing. It has been a common pattern that Reference::clear is called before or after enqueuing. I consider this a follow-up to JDK-8071507 that soft, weak, phantom references are automatically cleared references when implicitly or explicitly enqueued.
Webrev at: http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8175797/webrev.00/index.html Thanks Mandy
