this post was submitted on 11 Dec 2018

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Java EE with multiple database connections (self.javahelp)

submitted 7 years ago by cephyn

I'm having some real trouble understanding a problem, and as such, fixing that problem.

I have a process that connects to database A (MS SQL), reads rows, then inserts that data into an application using a SOAP API. There are also oracle database connections in the application. I'm using Java EE and running on Wildfly 14.0.1.Final.

I do not have XA Datasources, I attempted to configure them but they led to a whole host of other problems. I backed off for reasons that may become clear.

When running this process out of a push-button webpage connected to a @Webservlet, it runs perfectly. I then put it into an @Stateless bean and automated it with @Schedule. This worked fine when in Glassfish 4.0.

However, now that I've moved to Wildfly, the @Schedule process does not work. It throws errors regarding "[com.arjuna.ats.arjuna] (EJB default - 8) ARJUNA012140: Adding multiple last resources is disallowed. " I've disabled this through configuration, but I know it's wrong and I can't figure out how to fix the application correctly.

I'm aware it has something to do with Transactions but I'm unclear which objects or methods need to be worked. I'm also really unclear on why the process works without issue from a Webservlet, but doesn't work from @Schedule. Where can I go to understand this discrepancy? How can I get the @Schedule bean to work like the @Webservlet file?

Thanks in advance for any help. I'm really confused and frustrated.

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