How to do distributed transaction in java involving jdbc,jms and webservices

Question

I was asked the following question in an interview and couldn't answer that.

How do you include a jdbc operation,a web service call and a JMS operation into one single transaction. That means if one of them fails all has to be roll backed.

I have heard about two-phase commit protocol and oracl XA in case of database transactions involving multiple databases. But not sure whether the same can be used here.

Answer 1

The critical factor is that the web services you connect to have been built using a web services framework that supports transactions. JBoss Narayana is one such web services framework. Once the web services endpoint you are connecting to is on such a framework, it's just a matter of configuring spring to use the appropriate client.

In the case of Narayana, the spring config (from http://bgshinhung.blogspot.ca/2012/10/integrating-spring-framework-jetty-and.html) for transactions with web services:

Answer 2

You are never going to be able to do this in a completely bomb-proof way as the systems are separate. A failure in one stage of the system (for example between the SQL commit and the JMS commit the power on your server gets turned off) will leave the SQL commit in place.

The only way to resolve that would be to keep some record of partial commits somewhere and scan that on startup to fix any resulting problems but now what happens if you have a failure processing or keeping that list.

Essentially the solution is to do your own implementation of the multiple-stage-commit and rollback process wrapping the three operations you need to make. If any of the operations fails then you need to reverse (preferably using an internal transaction mechanism, if not then by issuing reversing commands) any that have been done so far.

There are a lot of corner cases and potential ways for a system like this to fail though, so really the first approach should be to consider whether you can redesign the system so you don't need to do this at all!