Detecting similar software applications

Although popular text search engines allow users to retrieve similar web pages, source code search engines do not have this feature. Detecting similar applications is a notoriously difficult problem, since it implies that similar highlevel requirements and their low-level implementations can be detected and matched automatically for different applications. We created a novel approach for automatically detecting Closely reLated ApplicatioNs (CLAN) that helps users detect similar applications for a given Java application. Our main contributions are an extension to a framework of relevance and a novel algorithm that computes a similarity index between Java applications using the notion of semantic layers that correspond to packages and class hierarchies. We have built CLAN and we conducted an experiment with 33 participants to evaluate CLAN and compare it with the closest competitive approach, MUDABlue. The results show with strong statistical significance that CLAN automatically detects similar applications from a large repository of 8,310 Java applications with a higher precision than MUDABlue.