RFR: 8188055: (ref) Add Reference::refersTo predicate [v5]

[David Holmes]

Hi Mandy,

On 20/10/2020 9:20 am, Mandy Chung wrote:
> On Mon, 19 Oct 2020 23:10:23 GMT, Mandy Chung <mchung at openjdk.org> wrote:
> 
>>> Looks good.
>>
>>> That's the crux of it: what exactly is meant by "the referent"? Does it
>>> mean the original object that was used as the referent, or does it mean
>>> the current value of the "referent" field inside the Reference (as get
>>> might return)?
>>
>> "the referent" is the object a `Reference` object refers to.
>>
>> as it's described in java.lang.ref package description:
>>
>>> Each reference-object type is implemented by a subclass of the abstract base Reference class. An instance of one of
>>> these subclasses encapsulates a single reference to a particular object, called the referent.
>>
>> See also `@return` in `Reference::get`:
>>> @return The object to which this reference refers, or null if this reference object has been cleared
> 
> I also personally prefer to use the "refers to" wording in the specification as well (IIRC I suggested that wordings).
> What about:
> 
> * Tests if this reference object refers to {@code obj}.
> * If {@code obj} is {@code null}, this method returns {@code true} if
> * this reference object was constructed with a {@code null} referent
> * or has been cleared.
> and
> @return {@code true} if {@code obj} is the object to which this reference refers,
>                or if {@code obj} is {@code null} and this reference has been cleared.

That looks good to me.

The CSR will need to be re-opened and updated unfortunately.

Thanks,
David

> -------------
> 
> PR: https://git.openjdk.java.net/jdk/pull/498
>