Rajesh, You should use the existing CloudStack DAO framework. If cloudstack will move to another ORM framework, it will have to be done in such a fashion that everything above the DAO layer doesn't have to change and the majority of the current DAO code do not have to change as well. Which would mean your code should migrate over along with the rest of the changes.
--Alex > -----Original Message----- > From: Rajesh Battala [mailto:rajesh.batt...@citrix.com] > Sent: Monday, July 02, 2012 10:59 PM > To: cloudstack-dev@incubator.apache.org > Subject: RE: Hibernate > > > > > -----Original Message----- > > From: Kelven Yang [mailto:kelven.y...@citrix.com] > > Sent: Saturday, June 30, 2012 3:31 AM > > To: cloudstack-dev@incubator.apache.org > > Subject: RE: Hibernate > > > > > > > > > -----Original Message----- > > > From: David Nalley [mailto:da...@gnsa.us] > > > Sent: Friday, June 29, 2012 10:37 AM > > > To: cloudstack-dev@incubator.apache.org > > > Subject: Re: Hibernate > > > > > > On Fri, Jun 29, 2012 at 12:13 PM, Rajesh Battala > > > <rajesh.batt...@citrix.com> wrote: > > > > > > > > > > > >> -----Original Message----- > > > >> From: David Nalley [mailto:da...@gnsa.us] > > > >> Sent: Friday, June 29, 2012 8:40 PM > > > >> To: cloudstack-dev@incubator.apache.org > > > >> Subject: Re: Hibernate > > > >> > > > >> On Fri, Jun 29, 2012 at 9:27 AM, Rajesh Battala > > > >> <rajesh.batt...@citrix.com> > > > >> wrote: > > > >> > > > > >> > Shall I proceed to replace Hibernate Framework with Spring JDBC. > > > >> > > > > >> > > > >> This is not a design decision to take lightly, or rush - as we've > > > >> talked about replacing the custom ORM that CloudStack uses as > > > >> well > > > >> - we'd want to make a decision on something that we are > > > >> comfortable with > > > in that role as well. > > > >> > > > > [Rajesh Battala] > > > > So we are planning to implement some ORM framework for CloudStack > > also? > > > > If so, then we need to evaluate the available ORM frameworks for > > > > java > > > which are based on Apache License? > > > > > > > > > > > > > I don't want to speak for Alex, but I have heard him mention such a > > > change number of times, and have seen it in his slides as well. > > > > > > But the larger sense is that if we are going to change something in > > > AWSAPI for communicating to the database, it should be something > > > that we are comfortable with adopting in the long term for the rest > > > of CloudStack, otherwise we'll end up with two different ways for > > > connecting to the database, which is fail. > > > > For Rajesh's concern in the short term (to get rid of Hibernate), we > > basically have following options, > > 1) Make the project depend on utils.jar in CloudStack and use existing > > CloudStack persistent layer. > > 2) Continue to make CloudBridge project independent > > a) use direct JDBC > > b) use Spring JDBC > > c) use ORM framework on Spring (i.e. OpenJPA etc) > > > > I vote on 2-b for a short term resolution. For a couple of reasons, > > > > The major reason is for adopting Spring, EC2/S3 API in the future may > > both need to support SOAP based web service API and REST API, Spring > > comes with support of both, in addition, it provides dependency > > injection, AOP and pluggable ORM framework, distributed transaction > management, etc. > > > > CloudBridge project has a very simple data model (it has only one > > table for EC2), original ORM (hibernate) usage is just for convenience > > (as Alex pointed that it tried to avoid direct SQL manipulation), on > > the other hand, giving the DAO abstraction, a limited amount of JDBC > > should not matter too much either. With Spring and already existing > > DAO abstraction, we can leave bigger ORM decision for the future. > > > > In the long term, ORM choice to us seems to be secondary > > consideration, giving the fact that our current custom ORM > > implementation serves its purpose well enough in CloudStack. But I do > > see the needs of more flexible dependency injection or transaction > > management framework in order to incorporate better integration with > > external transactional systems like message queue servers. I also see > > the needs of standardizing AOP patterns used in current CloudStack > > code base, Spring provides some good answers for that. So there is a > > possibility that it will be good for CloudStack to adopt it like many > > other Java communities do, so that we can focus on our own business > > logic and leave these external concerns to people who are doing it for a > living. > > > > Kelven > > > > > > > > > > --David > [Rajesh Battala] > > Please let me know conclusion of the thread. > I didn't see any reply to Kelven suggestions. > > Thanks > Rajesh Battala
