Need help with change

[Staffan Larsen]

On 22 maj 2013, at 06:35, David Holmes <David.Holmes at oracle.com> wrote:

> On 21/05/2013 11:56 PM, Coleen Phillimore wrote:
>> 
>> On 05/21/2013 09:29 AM, Staffan Larsen wrote:
>>> When doing heap iteration with JVMTI, the spec requires callbacks from
>>> the VM to the agent identifying the signers and protection domain
>>> references. This is what tagMap does, see jvmtiTagMap.cpp:2464.
>>> 
>>> As long as it it still possible for JVMTI to find these references
>>> (with ik->protection_domain() and ik->signers()), I think it's ok.
>> 
>> Okay.  Thanks for the quick answer.   I was going to rip this out (rats,
>> now I can't).  I can get to both protection domain and signers through
>> the mirror.
>> 
>> We are working on moving the signers completely to the jdk and not
>> having the jvm know about them at all.  Then we can't find the signers
>> through this interface.  Should we file a CCC request to change the
>> JVMTI spec then?
> 
> You can access any Java object field from the JVM - you just need to add it to java_classes.cpp :) I don't think you can just rip this out of the JVMTI spec.

I agree with David here - changing the JVMTI spec is not the solution.

/Staffan


> 
> David
> -----
> 
>> 
>> Thanks,
>> Coleen
>> 
>>> 
>>> /Staffan
>>> 
>>> 
>>> On 21 maj 2013, at 14:52, Coleen Phillimore
>>> <coleen.phillimore at oracle.com> wrote:
>>> 
>>>> I found during code review comment editing for my change that removes
>>>> signers and protection domain from the InstanceKlass, that JVMTI code
>>>> seems to have some sort of call back and knowledge of these fields in
>>>> instanceKlass.
>>>> 
>>>>          </constant>
>>>>          <constant id="JVMTI_REFERENCE_SIGNERS" num="5">
>>>>            Reference from a class to its signers array.
>>>>          </constant>
>>>>          <constant id="JVMTI_REFERENCE_PROTECTION_DOMAIN" num="6">
>>>>            Reference from a class to its protection domain.
>>>> 
>>>> 
>>>> If I remove these, will it cause incompatibilities?   It's used
>>>> during jvmtiTagMap.cpp (whatever that's doing).
>>>> 
>>>> Thanks,
>>>> Coleen
>>