Applying information-retrieval methods to software reuse: a case study

Reuse of existing software for new purposes is a key aspect of efficient software engineering. But finding opportunities for reuse can be difficult when building a large software system with pieces of a large previous system. Our approach is to match formal written "requirements" used to define the new software against requirements used to define the old software; requirement pairs with words in common suggest software-reuse opportunities. We explored two matching methodologies that use information-retrieval techniques. We tested our methods by comparing two US military systems, the Aviation Mission Planning System and the Joint Mission Planning System. Our second tool reduced the time to find 50% of the matching requirements by 99.4% compared to manual matching. (C) 2002 Elsevier Science Ltd. All rights reserved.