1. Formal Foundations of Software Evolution Workshop 1 Understanding Software Evolution using a Flexible Query Engine Michele Lanza Software Composition Group University Of Bern

2. Formal Foundations of Software Evolution Workshop 2 Environment The Query Engine A query returns “hits” from a large data collection A composite query can be composed of several (sub)queries by using logical operators The “basic” queries are based on type, name, properties and metrics A query can have an environment, i.e. subcondition(s) which must be fulfilled as well Moose, our Repository of Software Entities Query AND OR Query NOT Query

3. Formal Foundations of Software Evolution Workshop 3 Queries for Software Evolution Our repository can contain several versions of the same software in parallel In the context of Software Evolution, the queries aim at the differences and similarities between different versions of the same software entity The Queries must be fine-tuned and adapted to its context, i.e. the analyzed software

4. Formal Foundations of Software Evolution Workshop 4 The Problems of the Approach Renamed entities –different versions of the same entity do not have an explicit connection, WE must establish it. This may result in a possible loss of information The Queries still need: –a good formalism –a good naming scheme

5. Formal Foundations of Software Evolution Workshop 5 Conclusion & Future Work Conclusion: the approach works well, but... –needs more refinement –we need more experiences –we need a (standard) repository of Queries Future Work: further refine the Query Engine –internally: increase flexibility & adaptability –externally: Graphical User Interface