Re-engineering Legacy Systems From A Single Machine To A Distributed Architecture

With the progressive development of distributed application technology and because stand-alone legacy system cannot satisfy increasing requirement, many large-scale stand-alone legacy system needs to transform as distributed architecture system by reengineering. The outdated design, complex business logic, lack of related help document make enormous hinder for reengineering. This paper researched the way based on AOP method for reengineering, proposes the steps for operation method and implements a detailed solution. Encapsulate stand-alone legacy system data and expose as service interface, design client architecture based on MVVM, use WCF for distributed connection and also finish performance improvement.This paper mainly finish:(1)Analyze stand-alone legacy system architecture, module relation and business logic by reverse-engineering.(2)Combine with MVVM, describe WPF client by forward engineering.(3)link up C++legacy system with.Net distributed system by C++/CLI.(4)Describe common performance issues in distributed reengineering system and propose solution.This paper analyses the detailed process to reengineer stand-alone legacy system into distributed environment. This can effectively decrease the work, reduce reengineering complexity. Introducing MVVM architecture can decouple all levels relation, increase extensibility and code readability, enhance developing and testing efficiency. Use methods such as Lazy load, Selected Field to improve system performance and parallel processing ability.