Research on building software usage model based on UML model

Software usage model can be used as a guide when generate reliability test cases and it helps to evaluate the reliability of the software. Recent researches of deriving Markov Chain usage model from UML Model are mostly based on the UML sequence diagram and UML component diagram. But there are some problems with the existing methods: for some large software systems, there are many kinds of users who use the software in different ways, while a general usage model is not targeted and not suitable for all users. For this reason,this paper puts forward a new method to construct user-based software usage model. The method constructs usage model according to the UML activity diagram and UML use-case diagram, the model constructed by this method is user-based: the model describes, for every kind of users, the specific interacting process between the user and the system. What’s more, the model can be used to guide test cases generation.