3.2.2.4.2. Scoping Classes

If you need to deploy multiple versions of an application you need to use deployment based scoping. With deployment based scoping, each deployment creates its own class loader repository in the form of a HeirarchicalLoaderRepository3 that looks first to the UnifiedClassLoader3 instances of the deployment units included in the EAR before delegating to the default UnifiedLoaderRepository3. To enable an EAR specific loader repository, you need to create a META-INF/jboss-app.xml descriptor as shown in Example 3.9, “An example jboss-app.xml descriptor for enabled scoped class loading at the EAR level.”.

<jboss-app>
    <loader-repository>some.dot.com:loader=webtest.ear</loader-repository>
</jboss-app>

Example 3.9. An example jboss-app.xml descriptor for enabled scoped class loading at the EAR level.

The value of the loader-repository element is the JMX object name to assign to the repository created for the EAR. This must be unique and valid JMX ObjectName, but the actual name is not important.