Towards a type system for detecting never-matching pointcut compositions

Abstract

Pointcuts in the current AspectJ family of languages are loosely checked because the languages allow compositions of pointcuts that never match any join points, which developers are unlikely to intend, for example, set (* *)&&get (* *). We formalize the problem by defining well-formedness of pointcuts and design a novel type system for assuring well-formedness. The type of pointcuts is encoded by using record, union and the bottom types.