A Process to Combine AOM and AOP: A Proposal Based on a Case Study

Traditional object-oriented programming (OOP) paradigm focused on structuring systems into distinguished objects that work together to realize a system. However, when dealing with non-functional or quality requirements, such as security and fault tolerance, these are not easily structured into separate objects, but do rather crosscut a set of objects. Aspect-oriented programming (AOP) separate crosscutting concerns into single units called aspects. Aspect-oriented modelling (AOM) techniques allow system developers to design and verify an aspect-oriented system on the modelling level. During a case study of re-engineering an object-oriented system using aspect-oriented programming, we learned that well-designed aspect-oriented modelling (AOM) is essential to the success of aspect-oriented system. We also learned that current aspect-oriented programming tools (AOP) pose limitations on the design of an ideal aspect-oriented model. Based on lessons learned from this study we propose a process that handles aspects at two levels, both at the modelling level (AOM) and the programming language level (AOP). At the AOM level, aspects are identified and weaved together by AOM weaving to verify and do trade-off between different mechanisms. However, models are not woven together for the purpose of code generation based on a combined model. The actual weaving is done by the AOP compiler.