Ad removing finalize eventually (Re: JEP 411 Headaches: Instrumenting private methods in the JDK for authorization checkpoints.

[Rony G. Flatscher]

Peter,

On 27.07.2021 13:24, Peter Firmstone wrote:
> PhantomReference
>
> like this:
>
> https://github.com/pfirmstone/JGDMS/blob/trunk/JGDMS/jgdms-collections/src/main/java/org/apache/river/concurrent/ReferenceProcessor.java
>

thank you very much for the pointer!

---rony

>
> On 27/07/2021 8:01 pm, Rony G. Flatscher wrote:
>> Ad Alan's remark about eventually removing finalize in this thread:
>>
>> On 25.07.2021 16:44, Alan Bateman wrote:
>>
>> ... cut ...
>>> That said, there is strong desire to eventually remove finalization too. Finalization was
>>> deprecated several years ago and the Java platform defines APIs that provide much more flexible
>>> and efficient ways do run cleanup actions when an object becomes unreachable. So another
>>> multi-year/multi-release effort to remove a problematic feature, just nothing to do with this JEP.
>> ... cut ...
>>
>> A question: what alternatives are you thinking of?
>>
>> Background of the question: in an ooRexx-Java bridge for each Java object an ooRexx peer object gets
>> created and needs to exist as long as the Java object exists. Once the Java object gets garbage
>> collected the ooRexx peer object needs to be freed as well. The bridge between ooRexx (an
>> interpreted, message based, dynamically typed language) and Java is realized via JNI. Currently
>> (actually since 20 years) on the Java side the finalize method gets employed to signal to ooRexx
>> that its ooRexx peer object needs to be removed.
>>
>> So when you think of removing finalize and think of replacements for it, is there already a
>> replacement devised which can be used for determining that a Java "object became unreachable"/is not
>> referred to anymore/about to be garbage collected (or not being interacted with anymore for good)
>> and be able to communicate that fact/event? What would that be? Are there already discussions, ideas
>> about this somewhere?
>>
>> ---rony
>>
>> P.S.: I remember the comment back then that finalize although deprecated for use (not for removal)
>> for Java programs will not be removed as such use cases as described above need to use it.