valhalla-spec-observers Digest, Vol 23, Issue 10

A Z poweruserm at
Fri Mar 16 03:55:13 UTC 2018

I was wondering if there is an effort

to combine Java value types with

numeric mathematics and type operators?

Is this something anyone on the inside can comment on,


From: valhalla-spec-observers <valhalla-spec-observers-bounces at> on behalf of valhalla-spec-observers-request at <valhalla-spec-observers-request at>
Sent: Thursday, 15 March 2018 11:00 PM
To: valhalla-spec-observers at
Subject: valhalla-spec-observers Digest, Vol 23, Issue 10

Send valhalla-spec-observers mailing list submissions to
        valhalla-spec-observers at

To subscribe or unsubscribe via the World Wide Web, visit
valhalla-spec-observers Info Page -<>
All messages sent to the valhalla-spec-experts list are automatically forwarded to this list. Anyone may subscribe to this list, and any subscriber may post.

or, via email, send a message with subject or body 'help' to
        valhalla-spec-observers-request at

You can reach the person managing the list at
        valhalla-spec-observers-owner at

When replying, please edit your Subject line so it is more specific
than "Re: Contents of valhalla-spec-observers digest..."

Today's Topics:

   1. Questions about this email list. (A Z)
   2. Re: Nestmates: JEP 181 CSR request is ready for review
      (David Holmes)


Message: 1
Date: Thu, 15 Mar 2018 04:30:32 +0000
From: A Z <poweruserm at>
To: "valhalla-spec-observers at"
        <valhalla-spec-observers at>
Subject: Questions about this email list.
        <SL2P216MB058839DF29AD46E15E573EC59AD00 at SL2P216MB0588.KORP216.PROD.OUTLOOK.COM>

Content-Type: text/plain; charset="iso-8859-1"

Is this email list the place to pose informal questions and discussions

concerning Java Project Valhalla?

Is there anyone involved with the workings on the project

who can make any time to read and respond to public questions posed

about features of the project posed via this email list?


Message: 2
Date: Thu, 15 Mar 2018 19:19:43 +1000
From: David Holmes <david.holmes at>
To: valhalla-spec-experts at
Subject: Re: Nestmates: JEP 181 CSR request is ready for review
Message-ID: <ba9c2178-6c5e-5eb2-0594-b7a694908a0d at>
Content-Type: text/plain; charset=utf-8; format=flowed

After a number of minor editing tweaks to Class and MethodHandles, and
the more significant addition of the Security manager checks to Class,
the specs have again been updated.

I will propose the CSR request now so that we can start to get feedback
from that process.

Thanks for all the feedback so far.


On 9/03/2018 6:45 AM, David Holmes wrote:
> Thanks Mandy. We'll take the javadoc editing discussion off-list and
> I'll come back to the EG when any changes are made.
> David
> On 9/03/2018 5:33 AM, mandy chung wrote:
>> On 3/7/18 11:28 PM, David Holmes wrote:
>>> That's an interesting point. Should they also be @CallerSensitive?
>> Yes.
>> I hope SM::checkPackageAccess check will be removed some day as we now
>> have strong encapsulation. The security team has considered this and
>> requires further investigation.
>>> It may be we have to perform the SM check, but throwing
>>> SecurityException is somewhat contrary to the "no exceptions"
>>> approach of getNestHost().
>> The SecurityException will only be thrown when security manager is
>> installed and permission denies.?? Users are responsible to configure
>> the security policy to grant proper permission.
>>> I filed an issue to track this:
>>>> I suggest to make @apiNote in Class::getNestHost as just part of
>>>> javadoc.
>>>> It can define a section like "Nest Membership" that can be referenced
>>> My understanding is that @apiNote et al were introduced to more
>>> clearly distinguish between the actual specification part of the
>>> Javadoc and other non-normative text. As this is non-normative then
>>> @apiNote seems most appropriate. I presume we can still add a tag to
>>> allow cross-referencing from inside Class itself.
>> The definition of a nest is a specification that has no issue to
>> include in the javadoc.
>>>> by Lookup class spec.
>>> Cross-referencing internal text fragments across distinct javadoc is
>>> something I thought was not done. ??
>>>> I also have some suggested edits that you can
>>>> consider:
>>> Some of these are okay but this part:
>>> ? * The source language compiler is responsible for deciding which
>>> classes
>>> ? * and interfaces are nestmates. For example, the {@code javac}
>>> compiler
>>> is quite significant and should not be lost. A source compiler is
>>> free to chose not to use the new attributes (and of course not
>>> benefit from the new access control rules but continue to rely on
>>> access-bridges.) So the user of the API has to be aware of this.
>> This can be retained in @apiNote.
>>> And in MethodHandles I know there is a dislike of versioning text
>>> "Since JDK 11 ..." (though I see this as no different to using
>>> @since!), but again this new behaviour may or may not be present
>>> depending on the version of the classfiles and the compiler used to
>>> create them, so it is critical to me that this is very clearly
>>> stated. I suppose this could be re-stated in the form:
>>> "If the relationship between nested types is expressed directly
>>> through the {@code NestHost} and {@code NestMembers} attributes (see
>>> the Java Virtual Machine Specification, sections 4.7.28 and 4.7.29),
>>> then the associated {@code Lookup} object provides direct access to
>>> the lookup class and all of its nestmates. Otherwise, access between
>>> nested classes is obtained by the Java compiler creating a wrapper
>>> method to ..."
>> This is fine too. ? I still think a @linkplain to Class#nestmates
>> would be useful.
>> Mandy
>>> Thanks,
>>> David
>>>> Mandy
>>>> On 3/6/18 10:12 PM, David Holmes wrote:
>>>>> The Nestmates CSR request:
>>>>> has been prepared by Dan Smith and myself. Before Proposing this
>>>>> CSR request it needs to have Reviewers add themselves to it.
>>>>> (The first reviewer will need to edit the issue to enter their
>>>>> OpenJDK user name in the "Reviewed by" field. Subsequent reviewers
>>>>> can simply click on the "Reviewed by" field in the "People" section
>>>>> and add their user name.
>>>>> The CSR contains links to all the updated specification documents,
>>>>> all of which have been previously sent out for review/comment to
>>>>> the EG (and observers).
>>>>> Thanks,
>>>>> David

End of valhalla-spec-observers Digest, Vol 23, Issue 10

More information about the valhalla-spec-observers mailing list