In order to promote the understanding and evolution of a legacy software system

it is necessary to have an overall view of the structure.The common solution is to analyze the static source code by using clustering technique.In object-oriented software systems

however

due to the complexity of the software itself

such as exists of polymorphism and dynamic binding

and other factors

object's behavior actives need to be considered also.Use cases reflect the functionality of a system and play a key role in program comprehension.By clustering to establish the structural framework of the system

and by comparison with the actual design of the structure

our approach combines association rule mining techniques to obtain the mapping between use cases and corresponding events

and through the analysis of the static structure of use cases and related events invoked dependencies expansion.Finally

the experimental analysis of an open source project is evaluated and discussed to account for the applicability and effectiveness of our approach.