Scenario-based programming for ubiquitous applications

Ubiquitous applications usually involve highly interactive context data management. Traditional general-purpose programming languages are not sufficient for use in this domain, as they do not have the capability to manage such data effectively. We have developed a scenario-based programming language that we call 'PLUE (Programming Language for Ubiquitous Environment)', which is a Java-based prototyping language for ubiquitous application development. PLUE supports ECA (event-condition-action) rules and finite state automata-based (FSA-based) interactive responses to dynamic situations. In addition, PLUE programmers are able to manage heterogeneous data with a uniform view of path expressions. We have implemented PLUE on top of CAMUS (Context-Aware Middleware for Ubiquitous Robotic Companion System), a framework for context-aware applications that was originally developed for network-based robots.