Bilkent University
Department of Computer Engineering


Aspect-Oriented Evolution of Legacy Information Systems


Yasemin Satıroğlu

Master Thesis Presentation

 Supervisor: Prof. Dr. H. Altay Güvenir


In this thesis study, we provide a systematic process for analyzing the impact of crosscutting concerns on legacy systems. The process, which is called Aspectual Legacy Analysis Process (ALAP), consists of three sub-processes, Feasibility Analysis, Aspectual Analysis and Maintenance Analysis. All the three sub-processes consist of a set of heuristic rules and the corresponding control. Feasibility Analysis, which consists of two phases, describes the rules for categorizing legacy systems, in the first phase; and describes the rules for evaluating legacy systems with respect to the ability to implement static crosscutting and ability to implement dynamic crosscutting, in the second phase. The rules of the first phase are based on the categories of legacy systems that we have defined after a thorough study to legacy information systems, and the rules of the second phase are based on our discussion of these categories with respect to crosscutting implementation. Once the legacy system has been categorized and evaluated with respect to crosscutting implementation, the Aspectual Analysis sub-process describes rules for identifying and specifying aspects in legacy systems. Based on the results of the Feasibility Analysis and the Aspectual Analysis sub-processes, the Maintenance Analysis describes the rules for the selection of the appropriate legacy maintenance approach.

ALAP has been implemented in the Aspectual Legacy Analysis Tool (ALAT), which implements the rules of the three sub-processes and as such helps to support the legacy maintainer in analyzing a legacy system and a set of concerns, and identifying the appropriate maintenance approach.



Legacy Information Systems, Aspect-Oriented Software Development, Heuristic Rule Modeling

DATE: August 2, 2004, Monday @ 10:30