RFR: 8057752: WhiteBox extension support for testing

[Volker Simonis]

Hi everybody,

sorry for the late question, but I'm just looking at the WhiteBox API
and I'm wondering what this "extension support" is all about?

Currently WhiteBox::register_extended() is an empty method and the few
WhiteBox methods added with this change (e.g.
getHeapUsageForContext()) are neither registered in the VM nor are
they used in anywhere within the OpenJDK.

Does "extension" mean "Oracle proprietary" in this context (i.e. do
you have another WhiteBox::register_extended() in your closed sources
which register the mentioned functions)? Or did I misunderstand the
whole code?

Thank you and best regards,
Volker


On Wed, Sep 10, 2014 at 5:04 PM, Stefan Johansson
<stefan.johansson at oracle.com> wrote:
> On 2014-09-10 16:09, Christian Tornqvist wrote:
>>
>> Hi Stefan,
>>
>> This looks good.
>
> Thanks Christian.
> Stefan
>
>> Thanks,
>> Christian
>>
>> -----Original Message-----
>> From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On Behalf
>> Of
>> Stefan Johansson
>> Sent: Wednesday, September 10, 2014 7:35 AM
>> To: Mikael Gerdin; hotspot-dev at openjdk.java.net
>> Subject: Re: RFR: 8057752: WhiteBox extension support for testing
>>
>> Thanks for reviewing this Mikael.
>>
>> Made a small addition to allow Windows to handle empty extensions:
>> http://cr.openjdk.java.net/~sjohanss/8057752/webrev.00-01/
>>
>> Stefan
>>
>> On 2014-09-10 11:11, Mikael Gerdin wrote:
>>>
>>> Stefan,
>>>
>>> On Monday 08 September 2014 16.52.41 Stefan Johansson wrote:
>>>>
>>>> Hi,
>>>>
>>>> Please review these changes for RFE:
>>>> https://bugs.openjdk.java.net/browse/JDK-8057752
>>>>
>>>> Webrev:
>>>> http://cr.openjdk.java.net/~sjohanss/8057752/webrev.00/
>>>
>>> Looks good.
>>>
>>>> Summary:
>>>> Added the call to register_extended to make it possible extend the
>>>> WhiteBox API. The Java API is still defined in WhiteBox.java, if the
>>>> extension methods are not defined by an extension a linker error will
>>>> occur.
>>>
>>> Right, the code is designed so that it's possible to use mismatching
>>> versions of WhiteBox.java as long as you avoid calling the unlinkable
>>
>> methods.
>>>
>>> /Mikael
>>>
>>>> Stefan
>>
>>
>