An Arbortext Publishing Engine Java application is an object which implements the interface com.arbortext.e3.E3Application. It is loaded and invoked by the Arbortext PE Application Context (described in The Arbortext PE sub-process Application Context).

The Arbortext PE Request Manager invokes a Java application when it receives a request with the f query parameter set to java and the class parameter specifying the full Java class name of the application. When it receives such a request, the Arbortext PE Request Manager, by way of the predefined Request Handler and Java request function, allocates an Arbortext PE sub-process and passes the request to the Arbortext PE Application Context.