Incremental location of combined features for large-scale programs

The need for changing a program frequently confronts maintainers with the reality that no valid architectural description is at hand. To solve that problem, we presented at ICSM 2001 a language-independent and easy to use technique for opportunistic and demand driven location of features in source code based on static and dynamic analysis and concept analysis. In order to further validate the technique, we recently performed an industrial case study on a 1.2 million LOC production system. The experiences we made during that case study showed two problems of our approach: the growing complexity of concept lattices for large systems with many features and the need for handling compositions of features. This paper extends our technique to solve these problems. We show how this method allows incremental exploration of features while preserving the "mental map" the maintainer has gained through the analysis. The second improvement is a detailed look at composing features into more complex scenarios. Rather than assuming a one-to-one correspondence between features and scenarios as in earlier work, we can now handle scenarios that invoke many features.