A methodology for refactoring legacy code

Refactoring techniques have gained popularity due to their practical value in creating more agile code. Refactoring activities usually aim at improving the software quality, making them easier to understand, maintain, improvements on the software artifacts. Aspect-oriented programming (AOP) is receiving an increased attention due to its power in encapsulating crosscutting concerns. Refactoring allows reorganizing code while preserving the external behavior, while AOP facilitates modularizing crosscutting concerns in a system through use of a new unit of modularity called aspect. A combination of the two - aspect-oriented refactoring - helps in reorganizing code corresponding to crosscutting concerns to further improve modularization and get rid of the usual symptoms of crosscutting: code-tangling and code-scattering in legacy systems. The poorly designed procedural code when refactored with aspect orientation yields a better code. The aim of this paper is to establish a discipline for refactoring that will define the activities to be followed needed for refactoring. Our methodology is broken into two steps: first step is the preparation phase and the second is searching phase. This methodology is used by us in our research work. The set of activities described in this paper will help establish a proper refactoring procedure for the legacy code.