Dynamic Deployment of IIOP-Enabled Components in the JBoss Server

摘要

JBoss is an extensible Java application server that affords remote access to EJB components via multiple protocols. Its IIOP module supports IIOP-enabled EJBs, which are accessible both to RMI/IIOP clients written in Java and to CORBA clients written in various languages. While other systems use compilation-based approaches to generate IIOP stubs and skeletons, JBoss employs reflective techniques to avoid extra compilation steps and support on-the-fly deployment. CORBA/IIOP is a dynamic feature of JBoss in two senses: (ⅰ) the IIOP module can be dynamically deployed into a running server, and (ⅱ) IIOP-enabled EJBs are dynamically deployable components themselves. This paper presents the design of the IIOP module and describes the actions that module takes at EJB deployment time, including the creation of POAs, the instantiation of CORBA servants to implement IDL interfaces not known in advance, and the dynamic generation of HOP stub classes made available to Java clients via HTTP.