Mining system-user interaction traces for use case models

While code understanding is the primary program comprehension activity, it is quite challenging to recognize the application requirements from code, since they have usually been occluded by a set of layers of later implementation decisions. An alternative source of evidence, especially valuable for understanding the purposes for which the application was built, can be the dynamic behavior of the system, and more specifically the system-user interaction. We have developed a method for modeling the application behavior from the user's perspective in the form of use case models, using recorded traces of system-user interaction. We use data mining and pattern matching methods to mine these traces for frequently occurring user tasks. When interesting patterns are discovered, they are augmented with semantic information and they are used to build use case models. We demonstrate a successful application of this method to recover use case models from interaction traces with legacy 3270 systems to serve user interface reengineering activities.