User Interface Re-Engineering and Modernization Paradigms

Lecture 25 of SE602 Software Re-Engineering focuses on user interface (UI) re-engineering, transforming obsolete character-based green screens and archaic desktop GUIs into modern, responsive web and mobile interfaces. In many legacy systems, user interface logic is tightly coupled with core business computation and database access. The lecture examines modernization approaches: non-invasive screen scraping (intercepting character stream buffers and rendering graphical controls), interface wrapping via service adapters, and architectural refactoring using the Model-View-Controller (MVC) or Model-View-ViewModel (MVVM) patterns to isolate presentation concerns. Students evaluate cognitive usability, ergonomics, accessibility standards (WCAG), and responsive layout designs that preserve familiar operator keystroke workflows while providing intuitive modern user experiences across distributed enterprise environments. Scholars analyze Chidamber-Kemerer object-oriented metrics including WMC, CBO, and RFC to quantify the architectural impact of refactoring. Cloud migration pathways including rehosting, replatforming, and cloud-native refactoring are examined as extensions of legacy modernization. The relationship between technical debt accumulation, architectural degradation, and long-term enterprise software viability is reinforced. In this lecture, students examine formal methodologies, structural transformations, and analytical metrics of software re-engineering systems. Through detailed theoretical breakdowns, the lesson explores software evolution dynamics, legacy system preservation, and maintainability enhancement. Special emphasis is placed on reverse engineering workflows, abstract syntax tree construction, and program dependency representations. Mastering these foundational software re-engineering paradigms empowers software engineers to systematically revitalize enterprise legacy platforms. Analytical exercises and architectural traces help students prepare thoroughly for Virtual University midterm and final term examinations. The curriculum systematically aligns theoretical software evolution principles with practical source code modernization across industrial codebases. Reviewing the accompanying lecture handouts and metric tables reinforces understanding of coupling, cohesion, and architectural decay. Consistent evaluation of control flow graphs, call graph hierarchies, and database schemas ensures robust preparation for academic assessments. Students investigate the trade-offs between system replacement, wrapping legacy components, and iterative code refactoring transformations. The discussion highlights how Lehman laws of evolution, system complexity growth, and declining quality necessitate continuous code restructuring.