Re: [Springframework-developer] WLS 7 and TX suspend/resume - continue.

[Eugene K. <eu...@pl...>]

jürgen höller [werk3AT] wrote:

> I agree that it might not be following the intent of every J2EE vendor out
> there. However, it is still not too far-fetched to consider the JTA
> TransactionManager as a kind of extension to the UserTransaction interface:
> If a vendor's UserTransaction object implements the TransactionManager
> interface too, it usually should be fully usable, else the vendor should
> just provide a facade that solely implements UserTransaction...

   That is not my point. The point is if user is passing property A, why it 
should affect property B anyway? If he need to do something about B, why not 
to use that B at the first place (e.g. since it is all reflection, you can 
pass UserTransaction instance to TansactionManager setter, which will be more 
straightforward).

> Anyway, we can't easily turn off that autodetection by default, as some
> Spring users might rely on it. It also works nicely for a number of
> containers, for example Resin, Orion (OC4J), JOnAS (JOTM). And you can turn
> off autodetection now, via the "autodetectTransactionManager" flag,
> although the only case I know of where that is appropriate is the default
> JtaTransactionManager on WebLogic.

   It doesn't matter where it works. It looks like ugly hack anyway. :-)

> Regarding full autodetection of the J2EE server: While that certainly is
> achievable, it's not as straightforward as it may seem at first glance.

   Why is that?

> Migration between J2EE servers shouldn't be too hard anyway, as it just
> affects the JtaTransactionManager definition: The rest of the application
> can stay exactly the same. We currently leave it to the user to configure
> the JtaTransactionManager appropriately, and just include support classes
> for all sorts of cases.

   I didn't say it is hard, it just lead to multiple spring contexts - one per 
each application server and so far it is the only place where you have to do this.

   regards,
   Eugene


________________________________
> 
> Von: spr...@li... im Auftrag von
> Eugene Kuleshov Gesendet: So 05.09.2004 05:06 An:
> spr...@li... Betreff: Re:
> [Springframework-developer] WLS 7 and TX suspend/resume - continue.
> 
> 
> 
> jürgen höller [werk3AT] wrote:
> 
> 
>> Thanks, Thomas - it's great to have this for 1.1 final!
>> 
>> Did you have a chance to check whether WebLogic 8.1's UserTransaction 
>> object found at "java:comp/UserTransaction" implements the 
>> javax.transaction.TransactionManager interface too? It does so on
>> WebLogic 7.0. The benefit of such a scenario is that Spring's
>> JtaTransactionManager will autodetect the TransactionManager, without any
>> special setup.
> 
> 
> This autodetect feature looks like a half baked solution (or dirty hack). 
> You souldn't really rely on the fact that vendor choose to implement both 
> interfaces in publically available instance.
> 
> If you want to have smart tx proxy, it should autodetect j2ee container 
> vendor and version and then choose right way to retrieve tx proxy. Of
> course it has to be tested carefuly for each environment, but then users
> can really trust Spring's tx management and can use it without struggling
> with configuration for each environment type. That will also simplify
> moving application from one container to another (e.g. from Weblogic to
> Websphere).
> 
> 
>> I've documented the basic JTA setup options for popular J2EE servers in 
>> JtaTransactionManager's javadoc. It would be good to verify whether my 
>> autodetection comment just applies to WebLogic 7.0 or also to WebLogic
>> 8.1.
> 
> 
> 
> 
> regards, Eugene
> 
> 
> 
> 
> 
>> ________________________________
>> 
>> Von: spr...@li... im Auftrag von
>>  Thomas Risberg Gesendet: Sa 04.09.2004 17:42 An: 
>> spr...@li... Betreff: Re: 
>> [Springframework-developer] WLS 7 and TX suspend/resume - continue.
>> 
>> 
>> 
>> Juergen, Eugene,  Dimitry, all WLS 70 users,
>> 
>> We now have a new WebLogicServerTransactionManagerFactoryBean.  This bean
>>  factory looks up the ServerTransactionManagerImpl to get around the NPE 
>> that was thrown during a "forceResume".  I based the code on the
>> WebSphere variant.  This has been tested on WebLogic 7.0 SP5 and checked
>> in.  Here is a snippet from the configuration I tested with:
>> 
>> <!--  transaction manager --> <bean id="wls7tm"
>> 
>> class="org.springframework.transaction.jta.WebLogicServerTransactionManagerFactoryBean"/>
>>  <bean id="transactionManager"
>> 
>> class="org.springframework.transaction.jta.WebLogicJtaTransactionManager">
>>  <property name="transactionManager"> <ref local="wls7tm"/> </property> 
>> </bean>
>> 
>> Thomas
>> 
>> 
>> Thomas Risberg wrote:
>> 
>> 
>> 
>>> Juergen,
>>> 
>>> I'll try to implement and test a 
>>> WebLogicServerTransactionManagerFactoryBean today.  I'll keep you
>>> posted.
>>> 
>>> 
>>> For WLS 8.1 the TxHelper.getTransactionManager method is marked as 
>>> deprecated even though it is not documented as such in the JavaDocs. 
>>> There is also a brand new method getClientTransactionManager for 8.1
>>> that is starting out marked as deprecated.  Go figure.  We are probably
>>> better off recommending the JNDI lookups for 8.1.
>>> 
>>> Thomas
>>> 
>>> 
>>> 
>>> jürgen höller [werk3AT] wrote:
>>> 
>>> 
>>> 
>>>> Thanks, Thomas! This means that there *is* a way to make it work on 
>>>> WebLogic 7! Eugene, Dmitri, your pain finally has an end! :-)
>>>> 
>>>> Regarding obtaining the TransactionManager via the TxHelper on
>>>> WebLogic 7: That can easily be factored out into a custom
>>>> FactoryBean, like we did for WebSphere (see
>>>> WebSphereTransactionManagerFactoryBean), to be passed into
>>>> JtaTransactionManager's respectively WebLogicJtaTransactionManager's
>>>> "transactionManager" property. So we don't need a further
>>>> JtaTransactionManager subclass for this, just a further
>>>> TransactionManager lookup strategy.
>>>> 
>>>> BTW, Dmitri told me that the WebLogic UserTransaction object at 
>>>> "java:comp/UserTransaction" implements the TransactionManager
>>>> interface too, but that obviously forceResume doesn't work there... I
>>>> assume the ClientTransactionManagerImpl is returned there, not the 
>>>> ServerTransactionManagerImpl.
>>>> 
>>>> If we can double-check that this works better than the 
>>>> TransactionManager fetched from JNDI, I suggest to add a 
>>>> WebLogicServerTransactionManagerFactoryBean (or a similar name), 
>>>> clearly documenting that this is meant as an alternative to the 
>>>> standard JNDI TransactionManager reference that WebLogic provides, 
>>>> mainly for WebLogic 7. I wouldn't mind to do this even for the 1.1 
>>>> final release tomorrow...
>>>> 
>>>> Is the TxHelper lookup available on WebLogic 8.1 too? Of course, it 
>>>> shouldn't be necessary there, as the standard JNDI TransactionManager
>>>>  reference will work too. I just wonder whether it's available and
>>>> would work in principle: People could then configure a 
>>>> WebLogicServerTransactionManagerFactoryBean to be able to deploy on 
>>>> both WebLogic 7 and WebLogic 8, without adapting their Spring 
>>>> configuration.
>>>> 
>>>> Of course, such a WebLogicServerTransactionManagerFactoryBean would 
>>>> have to be coded via reflection to avoid compile-time dependencies on
>>>>  WebLogic, analogous to WebSphereTransactionManagerFactoryBean. Do
>>>> you have the chance to do this before tomorrow, Thomas?
>>>> 
>>>> Juergen
>>>> 
>>>> 
>>>> ________________________________
>>>> 
>>>> Von: spr...@li... im Auftrag
>>>>  von Thomas Risberg Gesendet: Sa 04.09.2004 14:30 An: 
>>>> spr...@li... Betreff: Re: 
>>>> [Springframework-developer] WLS 7 and TX suspend/resume - continue.
>>>> 
>>>> 
>>>> 
>>>> I have done some additional testing for this issue and this is what I
>>>>  have found.
>>>> 
>>>> WebLogic exposes a client TransactionManager implementation via JNDI 
>>>> (weblogic.transaction.internal.ClientTransactionManagerImpl) and in
>>>> WLS 7.0 it is throwing an NPE when you call forceResume (with or
>>>> without a suspended transaction that has been marked for
>>>> RollbackOnly).
>>>> 
>>>> They also have a different server implementation 
>>>> (weblogic.transaction.internal.ServerTransactionManagerImpl) that is 
>>>> returnd by a call to TxHelper.getTransactionManager().  With this TM 
>>>> the force resume works as expected.
>>>> 
>>>> So the workaround for now is to do the suspend/resume using the TM 
>>>> returned by TxHelper before calling the Spring managed code. 
>>>> Alternatively we could provide a WebLogic7JtaTransactionManager that 
>>>> uses this method of obtaining the TM.
>>>> 
>>>> I doubt that BEA will fix this issue in WLS 7.0.  They will probably 
>>>> suggest to upgrade to 8.1 or use the TxHelper to obtain the TM.
>>>> 
>>>> Thomas
>>>> 
>>>> 
>>>> jürgen höller [werk3AT] wrote:
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>>> Ideally, WebLogic should work properly with standard JTA 
>>>>> TransactionManager resume in all cases, not needing the proprietary
>>>>>  forceResume call. However, the least we can expect is that 
>>>>> forceResume works properly: You could send a corresponding bug
>>>>> report to BEA, for WebLogic 7.0. However, they might tell you that
>>>>> they fixed the issue in WebLogic 8.1...
>>>>> 
>>>>> Juergen
>>>>> 
>>>>> 
>>>>> ________________________________
>>>>> 
>>>>> Von: spr...@li... im
>>>>> Auftrag von jürgen höller [werk3AT] Gesendet: Fr 03.09.2004 23:31
>>>>> An: spr...@li... Betreff: Re: 
>>>>> [Springframework-developer] WLS 7 and TX suspend/resume - continue.
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> As I already wrote in my JIRA comments: Many thanks for your
>>>>> efforts, Dmitri!
>>>>> 
>>>>> I assume that with JtaTransactionManager, you'll get an 
>>>>> IllegalStateException ("cannot resume rollback-only transaction" or
>>>>>  the like), and with WebLogicJtaTransactionManager, you'll get the
>>>>> NPE in WebLogic code?
>>>>> 
>>>>> This really seems to be a bug in WebLogic 7.0... At least it should
>>>>>  work properly as long as not suspending a transaction that has
>>>>> been marked as rollback-only.
>>>>> 
>>>>> Juergen
>>>>> 
>>>>> 
>>>>> ________________________________
>>>>> 
>>>>> Von: spr...@li... im
>>>>> Auftrag von Dmitri Maximovich Gesendet: Fr 03.09.2004 23:07 An: 
>>>>> spr...@li... Betreff: 
>>>>> [Springframework-developer] WLS 7 and TX suspend/resume - continue.
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> I just tried WLS 7 with Spring 1.1rc2 and BMT transaction 
>>>>> demaraction. It doesn't work with standard JtaTransactionManager or
>>>>>  with WeblogicJtaTransactionManager, so something fundamentally
>>>>> broken in WLS7 (same NPE as described in JIRA SPR-251). Next I'll
>>>>> try to use WLS TransactionManager (exposed in JNDI) to
>>>>> suspend/resume transaction without Spring to see it it's going to
>>>>> work.
>>>>>