I understand. The concerns with the unmatched suspend/resume are known within WebSphere circles quite well. I'm sure IBM was one of the voices that objected to this functionality. :-)
I haven't had the time yet, but I want to understand the need for the suspend/resume functionality within OpenJPA. In my mind, it shouldn't be necessary. But, I haven't put a whole lot of thought into it yet... Kevin On 2/19/07, Craig L Russell <[EMAIL PROTECTED]> wrote:
Hi Kevin, Actually, I'll recant. This would not be a hack, because it does guarantee that the suspension of the transaction is only for the duration of the method call. IIRC, when we were discussing the functionality of the TransactionSynchronizationRegistry, and considered adding useful features like "suspend" and "resume", there were objections that this might result in unmatched suspend/resume pairs, which would be a reasonable use case. The biggest downside to the proposal here is that it requires more setup in a server environment. The suspend/resume component would have to be deployed in each ear where it was needed, or deployed as a shared component (which is still not portable Java EE behavior IIRC). Craig On Feb 19, 2007, at 12:37 PM, Kevin Sutter wrote: > Excellent use of the Java EE features! :-) > > Kevin > > On 2/19/07, Craig L Russell <[EMAIL PROTECTED]> wrote: >> >> It is possible to suspend a transaction by the standard Java EE >> technique. Unfortunately, this might be considered a hack, but AFAIK >> it's perfectly legal. >> >> The idea is to create an EJB component solely for the purpose of >> suspending a transaction. This could be a Stateless Session Bean that >> defines a method declared as Transaction Not Supported. The method >> invocation would contain a runnable as an argument which the >> execution of the method would then run. Once the runnable completed, >> returning from the method would resume the suspended transaction. If >> needed, an Object returned from the method could contain the results >> of the method. >> >> Craig >> >> On Feb 19, 2007, at 8:14 AM, Kevin Sutter wrote: >> >> > The WebSphere Transaction API does not allow for suspension of a >> > transaction. Even if we move to the "official" JPA transaction API >> > (TransactionSynchronizationRegistry), there is no suspend method >> > available. >> > I would have to better understand OpenJPA's need for the >> transaction >> > suspension before determining whether there are alternatives >> > available. >> > >> > On 2/16/07, Patrick Linskey <[EMAIL PROTECTED]> wrote: >> >> >> >> From what the user said, it sounds like another solution is to >> use a >> >> different ManagedRuntime that allows suspension. My guess is that >> >> this >> >> is not an "official" IBM API, and is the reason that we're not >> >> using it. >> >> Is there some other official means by which we could change >> >> WASManagedRuntime to allow suspend etc.? >> >> >> >> In short, if we solve OPENJPA-149, then we have the easiest-of-all >> >> pathways covered, and OPENJPA-153 is less important. >> >> >> >> -Patrick >> >> >> >> -- >> >> Patrick Linskey >> >> BEA Systems, Inc. >> >> >> >> >> _____________________________________________________________________ >> >> __ >> >> Notice: This email message, together with any attachments, may >> >> contain >> >> information of BEA Systems, Inc., its subsidiaries and >> >> affiliated >> >> entities, that may be confidential, proprietary, copyrighted >> >> and/or >> >> legally privileged, and is intended solely for the use of the >> >> individual >> >> or entity named in this message. If you are not the intended >> >> recipient, >> >> and have received this message in error, please immediately return >> >> this >> >> by email and then delete it. >> >> >> >> > -----Original Message----- >> >> > From: Albert Lee [mailto:[EMAIL PROTECTED] >> >> > Sent: Friday, February 16, 2007 11:21 AM >> >> > To: open-jpa-dev@incubator.apache.org >> >> > Subject: Re: WebSphere and transaction managers >> >> > >> >> > This is known problem in WAS. The reason is data source >> >> > created in WAS is >> >> > always enlisted in the current global transaction, therefore >> >> > RESOURCE_LOCAL >> >> > persistence unit using WAS data source triggers the observed >> >> behavior. >> >> > >> >> > This limitation will be corrected in the WAS EJB3 Feature >> >> > Pack and future >> >> > releases. >> >> > >> >> > Immediate solution is not to specify the non-jta-data-source >> in the >> >> > persistence unit but replace with connection information >> >> > using properties >> >> > openjpa.ConnectionUserName >> >> > openjpa.ConnectionPassword >> >> > openjpa.ConnectionURL >> >> > openjpa.ConnectionDriverName >> >> > >> >> > It is not the ideal solution, but functional. >> >> > >> >> > Albert Lee >> >> > >> >> > On 2/16/07, Patrick Linskey <[EMAIL PROTECTED]> wrote: >> >> > > >> >> > > Hi, >> >> > > >> >> > > It looks like the new WebSphere transaction manager lookup >> >> code is >> >> > > missing some functionality available elsewhere. >> >> > > >> >> > > See OPENJPA-149 >> >> > (https://issues.apache.org/jira/browse/OPENJPA-149) and >> >> > > OPENJPA-153 (https://issues.apache.org/jira/browse/ >> >> OPENJPA-153) for >> >> > > details. >> >> > > >> >> > > The key problems are: >> >> > > >> >> > > OPENJPA-149: the WASManagedRuntime class throws exceptions on >> >> some >> >> > > methods, preventing OpenJPA from being able to suspend >> >> transactions >> >> > > >> >> > > OPENJPA-153: even when specifying a non-JTA data source, >> >> > the data source >> >> > > returned does not allow commits. It does seem like the >> >> > behavior of the >> >> > > data source is at least a bit different than the JTA data >> >> > source, since >> >> > > OpenJPA is able to call setAutoCommit(). >> >> > > >> >> > > These seem like usability issues with WAS. I'm hoping that >> >> > someone with >> >> > > more WAS knowledge than me can resolve the issues easily. >> >> > Any takers? >> >> > > >> >> > > -Patrick >> >> > > >> >> > > -- >> >> > > Patrick Linskey >> >> > > BEA Systems, Inc. >> >> > > >> >> > > >> >> > ______________________________________________________________ >> >> > _________ >> >> > > Notice: This email message, together with any attachments, >> >> > may contain >> >> > > information of BEA Systems, Inc., its subsidiaries and >> >> > affiliated >> >> > > entities, that may be confidential, proprietary, >> >> > copyrighted and/or >> >> > > legally privileged, and is intended solely for the use of >> >> > the individual >> >> > > or entity named in this message. If you are not the >> >> > intended recipient, >> >> > > and have received this message in error, please immediately >> >> > return this >> >> > > by email and then delete it. >> >> > > >> >> > >> >> >> >> Craig Russell >> Architect, Sun Java Enterprise System http://java.sun.com/products/ >> jdo >> 408 276-5638 mailto:[EMAIL PROTECTED] >> P.S. A good JDO? O, Gasp! >> >> >> Craig Russell Architect, Sun Java Enterprise System http://java.sun.com/products/jdo 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp!
