Modeling the system-user dialog using interaction traces

It is generally the case that some user interface (UI) reverse engineering is needed for every non-trivial reengineering project. Typically, this is done through code analysis, which can be very difficult and/or expensive. When code analysis is not a must, as for wrapping purposes, system-user interaction can be an alternative input for the reverse engineering process. In the CelLEST project, we have developed a prototype, called LeNDI (Legacy Navigation Domain Identifier), to test this idea. LeNDI records traces of the legacy screen snapshots and user actions, while the user interacts with the legacy system. Then, it extracts a set of features for every snapshot and employs artificial intelligence methods to build a model of the legacy UI, called the state-transition graph. LeNDI uses two clustering methods to group similar snapshots together as one system screen modeled by one node on the graph. LeNDI uses the user actions recorded in traces to model the behavior of the legacy screens as the graph arcs. Evaluation results of this process are encouraging. The state-transition graph is used to classify each individual snapshot forwarded by the legacy system to the user while he interacts with it and is a main input to the forward engineering phase of the project.