Research Of Technology Of Component Online Evolution Based On Reflection

Many software systems are requested to provide uninterrupted service. The technology of online Software evolution is an important task in software maintenance. To provide uninterrupted service is to be an important guideline to evaluate software. This paper analyzes the development of soft evolution in the present situation, and researches software evolution at the component level, utilizes the introspection and feedback computing technology which is based on reflection. It proposes one kind of evolution component model, to implement component online evolution, and focused on the following aspects:First of all, it studies the correlated theories about component evolution. Firstly, the article studies the component-based software evolution. As a component is a separate coherent software module and component evolution in the highest flight. It researches the concept and technology of component evolution, and discusses the trend at the moment is online evolution.Secondly, it provides the evolution component based on reflection. To analyze the method of component online evolution, it refers the dynamic of component is key to online-evolution component. It develop component with introspective and adjustable by reflection mechanism, at runtime component behavior is on base of component mete description. The online evolution is achieved by modifying component mete description and reflecting to component behavior.Thirdly, it studies the key technology of component online evolution. It includes the control of request buffer, the dynamic loader, the state transfer between new and old object.The paper analyses the online-evolution component in the domain of personnel, and takes the experts committee system as the example, developing the online-evolution component base on reflective evolution component model. It has confirmed the component online evolution, the feasibility and the validity of the technology that has cited above.At last, this paper makes summary and some prospect about the future work aiming at the weak place of the research.