what is the structure of your EAR?
probably best if you could just post output of jar tf <name-of-ear>
also can you paste your application.xml?
My EAR contains one WAR and one EJB module. There are a bunch of JARs at the root of the EAR. I can't share any of the details.
All I want to do is control the order of class loading, so the classloader will look in one JAR before another.
I'm not sure about what vendor-specific behavior you'll find with WildFly, but for portable code, the Java EE 7 spec states that you can't count on ordering of classes. See EE 8.3 "Class Loading Requirements".
Then I'm curious how anyone uses Xstream in J2EE.
For now I have deleted the duplicate interfaces from the XmlPull JAR. I'm not entirely happy with that solution.
best thing you can do is have initialize in order set in application.xml
this way modules will be initialized in order that is specifed in application.xml