Hi Vladimir, yes, that's tricky. I can't say we have an elegant solution for that. I can't tell you what we do wrt EJB metadata (ejb-jar.xml/jboss.xml) as an example. For jboss.xml we have common JBossMetaData. http://anonsvn.jboss.org/repos/jbossas/projects/metadata/ejb/trunk/src/ma... It contains binding annotations but w/o the schema-level ones such namespace, etc. Then per schema version we create a top level class, e.g. http://anonsvn.jboss.org/repos/jbossas/projects/metadata/ejb/trunk/src/ma... http://anonsvn.jboss.org/repos/jbossas/projects/metadata/ejb/trunk/src/ma... There we specify the namespace and which properties we want to bind. So, actually, for some schemas common JBossMetaData contains more metadata than it is available in those schemas but those properties are just not bound for those schema versions. But the deployers regardless of the deployment descriptor version deployed use the same JBossMetaData API. In this case, though, it's only for the top-level class (root element). Although, we could have some tricks for other classes/elements as well. Other metadata (sub)projects (web, ear, rar, etc) use the same approach. (There are also tests for consistency between XSD/DTD and Java bindings, i.e. structural equivalence) What is a bit different, we don't include schema version in the namespace. Schema versions are different but the namespace stays the same. The same is true for JEE spec schemas. But even if we did, the current approach would still work. If you have some tricky cases/requirements then let's discuss them on the forums. It might be relevant to other projects as well. Best regards, Alexey On 5/11/2010 9:46 PM, Vladimir Blagojevic wrote: > Hi Alexey, > > Need an advice regarding best practices when it comes to XML schema management and references in configuration files. In infinispan project we have used JAXB annotated classes to annotate configuration pojos, automate manage configuration loading, and do schema creation. We have used the package-info.java files annotated with JAXB annotations to declare schema namespaces[1]. Then in turn we have generated XML schema file using JAXBContext#generateSchema. > > The current namespace is urn:infinispan:config:4.0, but this will change to urn:infinispan:config:4.1, urn:infinispan:config:5.0, etc in the future. What are our options for configuration file backward-compatibility? > > Best regards, > Vladimir > > > > [1] http://fisheye.jboss.org/browse/Infinispan/trunk/core/src/main/java/org/i...