Graphic Modelling Approach as a Support for Event-B Modelling

Event-B method, as an evolution of B-method, is a formal method for system-level modelling and analysis based on extended first order logic and set theory, which provides flexible approaches of refinement and decomposition to construct large systems gradually with some successful applications in their formal verifications. However, it is hard to manipulate and grasp this method for many researchers because of its highly abstraction. In order to reduce the burden of developers’ work and the complexity of Event-B model, a graphic modeling approach, called Event-B graph, is introduced in this paper, which is used as an alternative way to clearly describe the state flow of the model and provide a graphic way of system-level modelling to bridge the real problem and the Event-B model construction. After introducing some new concepts and structure of Event-B graph, the transformation algorithm from Event-B graph to Event-B model is provided and the equivalence of the transformation is then proved. An example is finally provided to illustrate the procedure of Event-B graph construction.