Subjective-C Bringing Context to Mobile Platform Programming

Thanks to steady advances in hardware, mobile computing platforms are nowadays much more connected to their physical and logical environment than ever before. To ease the construction of adaptable applications that are smarter with respect to their execution environment, the context-oriented programming paradigm has emerged. However, up until now there has been no proof that this emerging paradigm can be implemented and used effectively on mobile devices, probably the kind of platform which is most subject to dynamically changing contexts. In this paper we study how to effectively realise core context-oriented abstractions on top of Objective-C, a mainstream language for mobile device programming. The result is Subjective-C, a language which goes beyond existing context-oriented languages by providing a rich encoding of context interdependencies. Our initial validation cases and efficiency benchmarks make us confident that context-oriented programming can become mainstream in mobile application development.