NORA / HAMMR : Making Deduction - Based SoftwareComponent Retrieval Practical yBernd

Deduction-based software component retrieval uses pre-and postconditions as indexes and search keys and an automated theorem prover (ATP) to check whether a component matches. This idea is very simple but the vast number of arising proof tasks makes a practical implementation very hard. We thus pass the components through a chain of lters of increasing deductive power. In this chain, rejection lters based on signature matching and model checking techniques are used to rule out non-matches as early as possible and to prevent the subsequent ATP from \drowning." Hence, intermediate results of reasonable precision are available at (almost) any time of the retrieval process. The nal ATP step then works as a connrmation lter to lift the precision of the answer set. We implemented a chain which runs fully automatically and uses MACE for model checking and SETHEO as ATP and evaluated it over a medium-sized collection of components. The results connrm the practicality of our approach.