Customizing IDL mappings and ORB protocols

Current mappings of IDL to implementation languages such as C++ or Java use CORBA specific data-types, which makes it imperative for an object implementation to be CORBA-compliant. While being completely CORBA-compliant ensures portability and interoperability, several classes of enterprise applications may only require interoperability with other CORBA applications. Other applications may be constrained by such factors as a large existing code-base or a widely used communication protocol. In many cases, these applications can benefit from the concise expressiveness of IDL without committing to the overhead of using a general-purpose CORBA ORB. To aid this process, we propose a new approach to ORB design where the IDL mapping and ORB protocol is completely configurable. As a motivation, we present our use of IDL in the development of a large in-house application. In this application, all interfaces are specified using IDL, which is mapped to C++ using a custom mapping. We then present an architecture for a template-driven IDL compiler and describe the implementation of a prototype we built. With this compiler architecture, an IDL mapping can easily be specified and customized by writing an appropriate template.