Apache Tomcat 6 是否支持 JTA？

Question

I have some confusion on using JTA within the Spring Framework on Apache Tomcat and i hope someone will clarify as after many research i can't seem to find the correct answer as of yet.

I am developing a web application using Spring Framework to be running on Apache Tomcat 6.

I read somewhere that Spring's does support for JTA but it delegates to the underlying JavaEE application server. Now this is where i am confused because i Tomcat is not a full JavaEE application server - it is merely a servlet container and as i believe it doesn't provide JTA implementation like the full JavaEE application server (Glassfish/Wildfly etc...) does.

But when i do something like the following the transaction aspect of it works:

@Transactional
public class ServiceClassImpl implements ServiceInterface {
// code here that involves transactions e.g. calling DAO code
...
}

So, i'm confused. I hope someone will enlighten me.

Answer 1

The answer is: NO. Tomcat 6.x (7&8) don't provide JTA out-of-the-box because they don't have a transaction manager which is required as a separate component to monitor multiple resources (eg datasources).

The mentioned answer How to use JTA support in Tomcat 6 for Hibernate? already gives a list of additional JTA transaction managers that can be used alongside Tomcat.

Spring supports declarative transaction management via a platform transaction manager (TM) and provides some implementations (eg datasources) that make @Transactional work on a single resource without the additional TM.

Understanding the Spring Framework transaction abstraction provides more details and Spring Boot can be easily configured to run Atomikos or Bitronix Transaction managers on the embedded Tomcat.

Answer 2

JTA 为您提供了分布式事务支持，但是如果 JTA 不像 Tomcat 那样可用，您仍然可以使用本地 JDBC 事务。

Answer 3

YES :-)

JTA can be used in Tomcat, for instance via https://www.atomikos.com

The trick is to use a componentized JTA implementation.

Cheers