Towards a Catalogue of Refactorings and Code Smells for AspectJ

Abstract

Abstract. In this paper, we contribute to the characterisation of a programming style specific to aspect-oriented programming. For this purpose, we present a collection of refactorings for aspect-oriented source code, comprising refactorings to enable extraction to aspects of crosscutting concerns from objectoriented legacy code, the subsequent tidying up of the extracted aspects and factoring out of common code from similar aspects to superaspects. The second group of refactorings is documented in detail. In addition, we propose some new aspect-oriented code smells, including one smell that is specific to aspect modules. We also propose a reinterpretation of some of the traditional objectoriented code smells in the light of aspect-orientation, to detect the presence of crosscutting concerns.

Object-oriented transformations for extracting aspects

“…Monteiro and Fernandes have described a set of refactorings for extracting crosscutting concerns, restructuring the internals of aspects and dealing with inheritance hierarchies of aspects [23][24][25]. Another well-known catalog of aspect-oriented refactorings was proposed by Laddad [21].…”

“…As a consequence, several works have been developed in two areas that are critical when migrating to this new technology: aspect mining [6,19,34] and aspect-oriented refactoring [21,16,24,25]. The purpose of aspect mining techniques is to identify crosscutting concerns in legacy, non-aspect-oriented code.…”

“…For example, in one of the first papers about aspect-oriented refactoring, Monteiro recognizes that ''it is sometimes necessary to refactor the base code in order to expose the necessary join points to AspectJ" [23]. However, even in Monteiro more recent papers, this necessity is not investigated in details [24,25]. prepare the software system is undertaken" [26].…”

Guidelines for Enabling the Extraction of Aspects from Existing Object-Oriented Code.

“…However, the author has not documented such refactorings in details, even in further work [16]. More recently, Monteiro and Fernandes have proposed a refactoring process to guide the transformation of a Java source code base into a functionally equivalent AspectJ source code base [17].…”

Modularity-Oriented Refactoring

“…Code smells are ways to describe warning signs about potential problems in code [1,5]. One of the purposes of refactoring is precisely eliminating code smells.…”