Can tx:jta-transaction-manager
use id as name so that I can pass it as REF to my service layer like below?
The <tx:jta-transaction-manager>
exposes the transaction manager as a Bean in the Spring context with the name "transactionManager
".
Can tx:jta-transaction-manager
only be used with a J2EE container?
Quoting the Chapter 9. Transaction management from the Spring documentation:
Is an application server needed for transaction management?
The Spring Framework's transaction
management support significantly
changes traditional thinking as to
when a J2EE application requires an
application server.
In particular, you don't need an
application server just to have
declarative transactions via EJB. In
fact, even if you have an application
server with powerful JTA capabilities,
you may well decide that the Spring
Framework's declarative transactions
offer more power and a much more
productive programming model than EJB
CMT.
Typically you need an application
server's JTA capability only if you
need to enlist multiple transactional
resources, and for many applications
being able to handle transactions
across multiple resources isn't a
requirement. For example, many
high-end applications use a single,
highly scalable database (such as
Oracle 9i RAC). Standalone transaction
managers such as Atomikos Transactions
and JOTM are other options. (Of course
you may need other application server
capabilities such as JMS and JCA.)
The most important point is that with
the Spring Framework you can choose
when to scale your application up to a
full-blown application server. Gone
are the days when the only alternative
to using EJB CMT or JTA was to write
code using local transactions such as
those on JDBC connections, and face a
hefty rework if you ever needed that
code to run within global,
container-managed transactions. With
the Spring Framework, only
configuration needs to change so that
your code doesn't have to.
So, as explained in the third paragraph, if you want to work with multiple transactional resources, you'll need global transactions which involve a JTA capable application server. And JTA capable application server means a real J2EE container or a non J2EE container (like Tomcat) with a standalone transaction manager like Atomikos, JOTM, Bitronix, SimpleJTA, JBossTS or GeronimoTM/Jencks.
FWIW, I've seen lots of complains about JOTM, I think that GeronimoTM/Jencks lacks of documentation, I can't really say anything about JBossTSArjunaTS (except that it's a rock solid product), SimpleJTA and Bitronix have both good documentation and Atomikos is an impressive product greatly documented too. Personally, I'd choose Bitronix or Atomikos.
PS: Honestly, if this sounds like Chinese to you, you should maybe consider using a single database (if this is an option, go for it!) or consider using a real J2EE container like JBoss or GlassFish as I wrote in a previous answer. No offense but all this JTA stuff is not trivial and taking the JOTM path is not that simple if you don't really understand why you need it.