Detecting and investigating the source code changes using logical rules

Software developers often need to examine program differences between two versions and reason about the changes. Analyzing the changes is the task. To facilitate the programmers to represent the high level source code changes, this proposed system introduces the rule-based program differencing approach to represent the changes as logical rules. This approach is instantiated with three levels: first level describes the changes in method header names and signature; second level captures change in the code level and structural dependences; and third level identifies the same set of function with different name. This approach concisely represents the systematic changes and helps the software engineers to recognize the program differences. This approach can be applied in open source project to examine the difference among program version.