Reference: Rice, J. Writing an OKBC Application--A Case Study. Knowledge Systems Laboratory, May, 1998.
Abstract: Open Knowledge-Base Connectivity (OKBC) is an API that allows knowledge applications to talk to servers with knowledge content. The API has client implementations in Java, Lisp and C, and server implementations in both Java and Lisp. The OKBC specification contains a specification for what is called the "Front End API", that is, the API used to write applications, as opposed to the API used to establish bindings between OKBC and the knowledge content on a Knowledge Representation System (KRS).
The OKBC specification is a thorough and formal document, and although it gives a clear definition of the front end API, in practice it gives the reader no clues about how to set about writing an OKBC application. In this paper we show a simple, but non-trivial OKBC application developed in multiple languages - a Knowledge Base (KB) summarizing tool, which given an arbitrary OKBC KB will generate a page of HTML showing the contents of that KB. We develop this application in four different ways to show different aspects of OKBC application authoring, and how an application can be progressively optimized.
Full paper available as zip.