cloudstack-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Kelven Yang <kelven.y...@citrix.com>
Subject Re: [DISCUSS] @DB and @ActionEvent
Date Tue, 03 Sep 2013 23:35:15 GMT
One correction, it should be "usage of @ActionEvent is not compatible to
proxy based AOP". 

Proxy based AOP is suitable if there is no re-entrance from one
interception point to another one of the same object. But most of
@DB/@ActionEvent semantics are implemented by relying on general method
interception.

Kelven 

On 9/3/13 3:58 PM, "Kelven Yang" <kelven.yang@citrix.com> wrote:

>
>
>On 9/3/13 3:41 PM, "Darren Shepherd" <darren.s.shepherd@gmail.com> wrote:
>
>>On 09/03/2013 03:05 PM, Kelven Yang wrote:
>>> The only purpose for @DB is to provide a transaction context
>>> automatically(open/close) in thread's calling stack. We can fully get
>>>rid
>>> of it if we guard it from the entry point of every runnable. A little
>>> caution though, we have a couple places that involve with switching
>>> between Cloud DB instance and usage DB instance.
>>
>>I'll pay extra attention to that.
>>
>>> Unfortunately, @ActionEvent is not compatible to proxy based AOP, the
>>> information it generates is not only informational for debugging
>>>purpose.
>>> Some business logic (auditing or billing) depend on it. You probably
>>>need
>>> to be careful. Whatever change you want to make, it should not break
>>>the
>>> semantics of generating correct events for its business logic users.
>>
>>I have no intention of changing the semantics.  I'll see how I can
>>ensure that the changes don't have any impact through some programmatic
>>verification.
>
>That sounds great!.
>-Kelven
>
>>
>>Darren
>>
>


Mime
View raw message