RFR [9] 8140687: Move @Contended to the jdk.internal.vm.annotation package

[Peter Levart]

On 11/09/2015 11:43 AM, Chris Hegarty wrote:
> On 02/11/15 10:45, Aleksey Shipilev wrote:
>> On 11/02/2015 02:56 AM, Chris Hegarty wrote:
>>> In line with the intended location for other VM annotations,
>>> see 8138732 [1], @sun.misc.Contended should be moved
>>> to the jdk.internal.vm.annotation package.
>>>
>>> http://cr.openjdk.java.net/~chegar/8140687/00/
>>
>> Changes look good to me.
>>
>> But what's the compatibility story for JSR 166? With this move, we would
>> be unable to bootclasspath JSR 166 JAR, since it references the "old"
>> sun.misc.Contended?
>
> Correct.
>
> As you are aware, the 166 CVS will fork shortly to support
> a JDK 9 only version. Artifacts built from the fork are of
> course not impacted by this change.
>
> For existing 166 artifacts, they will not run on JDK 9 as
> the Contended annotation will not be present.

Note that they might actually be able to run. They would just not be 
@Contended. As I understand, VM just checks the presence of annotations 
by string value - it doesn't try to materialize them in the form of 
objects, so it does not fail.

Regards, Peter

>
> -Chris.
>
>> Thanks,
>> -Aleksey
>>