On Tue, 8 Dec 2020 02:36:01 GMT, Mandy Chung <mch...@openjdk.org> wrote:
> `Reference::isEnqueued` method was never implemented as it was initially > specified since 1.2. The specification says that it tests if this reference > object has been enqueued, but the long-standing behavior is to test if this > reference object is in its associated queue, only reflecting the state at the > time when this method is executed. The implementation doesn't do what the > specification promised, which might cause serious bugs if unnoticed. For > example, an application that relies on this method to release critical > resources could cause serious performance issues, in particular when this > method is misused on Reference objects without an associated queue. > `Reference::refersTo(null)` is the better recommended way to test if a > Reference object has been cleared. > > This proposes to deprecate `Reference::isEnqueued`. Also the spec is updated > to match the long-standing behavior. > > CSR: https://bugs.openjdk.java.net/browse/JDK-8189386 This change looks good. There are a couple of tests that are using isEnqueued. vmTestbase/gc/gctests/ReferencesGC/ReferencesGC.java jdk/java/lang/ref/ReferenceEnqueue.java https://bugs.openjdk.java.net/browse/JDK-8257876 (I'm working on this.) ------------- Marked as reviewed by kbarrett (Reviewer). PR: https://git.openjdk.java.net/jdk/pull/1684
