关键词: 普适计算, 中间件, 自适应, 策略, 构件, 计算反射

Abstract: Middleware is an important method for software self-adaptation， which should provide not only the general built-in self-adaptation mechanisms， but also the development and runtime supports for application of specific ones. This paper addresses the self-adaptation problem in ubiquitous computing software by using the principal of separation of concerns and introducing policies to model the software self-adaptation processes. The policy-based software self-adaptation concept model and the adaptation-enabled， base-meta level divided light weight component model are proposed， based on which a policy-based software self-adaptation framework is designed and implemented on a ubiquitous self-adaptation middleware named UbiStar. The framework provides the development and runtime supports for ubiquitous applications compliant to above models， and thus enables effectively for application-specific software self-adaptation processes.

Key words: ubiquitous computing, middleware, self-adaptation, policy, component, computing reflection