构件演化中的系统行为一致性的研究

Study on Behavior Consistency of System on Component Evolution

构件技术的发展,减少了开发应用程序的时间和复杂度,同时也为软件提供了更好的动态演化能力。基于构件的软件系统是通过在构件间建立交互关系,将多个构件组织成一个统一的整体得到的。因此在构件演化时,例如对构件功能实现进行改变,可能导致系统运行偏离原来的系统行为。我们的工作就是在构件演化时对系统行为进行一致性检查,保证构件的功能实现的变化不会使系统行为偏离原来的系统。在本文中首先通过Petri-net的形式化方法,对系统实现中包括的构件的功能实现和构件间的交互进行建模,并通过以上信息推导得到系统行为。在此基础之上,根据基于行为继承理论的行为一致性规则的要求对定义的系统功能行为进行验证,以保证构件演化时系统行为的改变符合行为的一致性要求,同时又保证了构件演化的灵活性。

Component based software development （CBSD） facilitate the construction of software and support dynamic evolution. In CBSD, software is built by assembling components which are already developed and prepared for integration, so the software system behavior is changed with component evolution. Our work is to verify system behavior and ensure behavior consistency of system. At first, component behavior and interaction between components are formalized by Petri-net, and then, system behavior is verified by consistency rule based on behavior inheritance theory. In this way, system behavior is consistent when component is evolving.