Integrating Prototyping into the SOFL Three-Step Modeling Approach

Writing formal specifications in a practical software project is likely to increase the time for requirements analysis and/or abstract design and to postpone the implementation, which is often hard to be accepted by the user and/or the manager of the project. Prototyping provides an agile approach for communication between the user and the developer but is unable to deal with all aspects of the system precisely and completely. In this paper, we put forward a new development approach resulting from integrating prototyping techniques into the SOFL three-step modeling approach. The new approach is aimed at achieving a quality development process through promoting the facilities for user-friendly communication between the user and the developer and for exploring all possible aspects of the system precisely. We have applied the approach to develop an IC card software for the Japan railway service system and present the recorded data as the result of the study. Compared to our previous experiences using both formal and informal methods, our study suggests that the new approach can be more practical than existing formal specification methods and more effective in achieving the completeness and accuracy of the user’s requirements than informal specification methods.