Software Evolution Technology Research And Application

The traditional software architecture essentially is static and isolated and the software entities lack dynamic adaptation ability, autonomy and dynamic coordination. So it is difficult to adapt the open, dynamic and changing Internet environment. Software evolution and coordination theory is studied in this paper and the research results are applied in our practical system development successfully.A survey of software evolution and its impact on software lifecycle is presented in this paper. For design-time evolution, a detailed discussion of the T-MAP Traffic map framework is presented to illustrate the working mechanisms of a practical framework product. T-MAP applies "hot-spot" theory to improve its design-time evolution capability.The traditional research on dynamic evolution focuses on improving software' s continuous availability and lacks support for distributed system environment. This paper discusses the basic model and implementation problems of distributed evolution system from the view of distributed coordination. DynamicArch, A dynamic architecture supporting distributed evolution and coordination, is presented and a complete DynamicArch supporting environment is developed. Some independent DynamicArch systems can form a distributed DynamicArch system. Each DynamicArch system has complete support for single-process dynamic evolution and the distributed dynamic evolution and coordination is achieved by the negotiation mechanism between the DynamicArch systems. The software system based on DynamicArch has excellent dynamic adaptation ability and can adapt easily to various changes, including planed and unplanned changes. An application of DynamicArch in a working subsystem: City Traffic TV Monitor System in our project Dalian City Traffic Fast-Response System, is presented. The successful application verifies our initial design of DynamicArch. DynamicArch is the first step in the way to an open dynamic Internet coordination environment. The future research directions of DynamicArch are discussed in the end of this paper.