Join point designation diagrams: a visual design notation for join point selections in aspect-oriented software development

Sharing knowledge about program specifications is a crucial task in collaborative software development. Developers need to be able to properly assess the objectives of the program specification in order to adequately deploy or evolve a piece of program. The specification of join point selections (also known as "pointcuts") in Aspect-Oriented Software Development (AOSD) is a piece of a program which frequently tends to grow quite complex, in particular if the join point selections involve selection constraints on the dynamic execution history of the program. In that case, readers of the pointcut specification frequently find themselves confronted with considerable comprehension problems because they need to inspect and realize an intricate and fragmented program specification in order to reconstruct the true objectives of the join point selection. This thesis presents Join Point Designation Diagrams (JPDDs) as a possible solution to the problem. JPDDs are a visual notation that provides an extensive set of join point selection means which are consolidated from a variety of contemporary aspect oriented programming languages. JPDDs are capable of highlighting different join point selection constraints depending on the conceptual view on program execution which underlies the join point selection. With the help of these means, JPDDs are capable of representing complex join point selections on the dynamic execution of a program in a succinct and concise manner. JPDDs may be used by software developers of different aspect oriented programming languages to represent their join point selections for the sake of an improved comprehensibility of the join point selections and – thus – for the sake of an easier communication between software developers. This thesis gives empirical evidence that JPDDs indeed facilitate the comprehensibility of join point selections. To do so, it conducts a controlled experiment which compares JPDDs to equivalent pointcut implementations in an aspect oriented programming language. The experiment shows that JPDDs have a clear benefit over their codified counterparts in most of the case, while only in few cases no such benefit could be measured.