AspectJML: modular specification and runtime checking for crosscutting contracts

Aspect-oriented programming (AOP) is a popular technique for modularizing crosscutting concerns. In this context, researchers have found that the realization of design by contract (DbC) is crosscutting and fares better when modularized by AOP. However, previous efforts aimed at supporting crosscutting contract modularity might actually compromise the main DbC principles. For example, in AspectJ-style, reasoning about the correctness of a method call may require a whole-program analysis to determine what advice applies and what that advice does relative to DbC implementation and checking. Also, when contracts are separated from classes a programmer may not know about them and may break them inadvertently. In this paper we solve these problems with AspectJML, a new specification language that supports crosscutting contracts for Java code. We also show how AspectJML supports the main DbC principles of modular reasoning and contracts as documentation

Modular Aspect-Oriented Design Rule Enforcement With Xpidrs

Aspect-oriented programming (AOP) is a popular technique for modularizing crosscutting concerns. However, constructs aimed at supporting crosscutting modularity may break class modularity. For example, to understand a method call may require a whole-program analysis to determine what advice applies and what that advice does. Moreover, in AspectJ, advice is coupled to the parts of the program advised, the base code, so the meaning of advice may change when the base code changes. Such coupling also hinders parallel development between base code and aspects. We propose some simple modifications to the design of crosscut programming interfaces (XPIs) to include expressive design rule specifications. We call our form of XPIs crosscutting programming interfaces with design rules (XPIDRs). The XPIDR-based approach, by design, supports modular runtime checking and parallel development by decoupling aspects from base code. We also show how XPIDRs allow specification of interesting control flow effects, such as when advice does (or does not) proceed. We have implemented XPIDRs as a simple contract extension to AspectJ. Since XPIDRs do not require any new AspectJ constructs, they can be adopted easily by the AspectJ community. Copyright © 2013 ACM