Application And Research On Design Pattern In Software Reuse

Software reuse has been regarded as a feasible way to solve software crisis and to improve both productivity and quality, which receives more attention. Technology of CBD carries on design and implementation based on components, and improves developing independence of each part in application system. However, CBD has some limitations in application of reuse because of variability of system requirements and condition restriction of CBD itself. Design pattern, which focuses on encapsulating the concept that varies, makes a system have not only high cohesion and loose coupling, but also flexibility and reusability. Design pattern supports reuse at a higher level.The paper studies and summarizes the theory and technology of software reuse, and discusses the domestic and foreign present situation as well as key factors for achieving software reuse. It emphasizes technology of component and characteristics of CBD. And then the paper makes further research on design pattern, mainly including its characteristic, applicability and supports to Object-Oriented Reuse.As a major part, the paper analyzes inadequacy of CBD in software reuse and uses design pattern to make improvement, then summarizes the principles of reuse based on pattern, and proposes a method guiding reuse with pattern. The paper also studies how to implement variability of component based on design pattern, and analyzes feasibility of implementing software reuse with the combining of pattern and component, then gives an approach to selecting patterns and applies it to reuse.As an example, the paper uses development of software project management system to discuss the application of software reuse based on design pattern in actual project. After making domain analysis and architecture analysis according to the new CBD model improved with design pattern, some reasonable components are derived and improved with appropriate patterns, which has good reuse effect.The result indicates that the new CBD model improved with design pattern implement software reuse well, so it is feasible in application.