Analysis and implementation of software reuse measurement

Software reuse has been shown to increase quality and productivity [Card et al 86] [Browne et al 90] [Frakes 91] [Agresti and Evanco 92]. As researchers and development organizations begin to recognize the potential benefits of systematic reuse of software, formal measures of the amount of reuse in a given system or subsystem are needed. A formal measurement of software reuse will provide software developers and managers with the necessary data to track reuse progress. This project and report describe such a measurement of parts-based reuse, building upon the reuse level metric and the rl software tool as described by Frakes in [Frakes 90] and [Frakes 92].

This paper reviews the current research literature in the areas of software reuse and software reuse metrics. The reuse metrics proposed by Frakes are extended to include reuse frequency and a reuse complexity weighting. The metrics are formally defined. Results from extensive testing of rl are reported and correlated with program size. The enhancements made to the rl program include:

Specification of the reuse frequency metric,

An additional call graph abstraction for reuse measurement,

Weighting of software components for complexity,

Allowing the user to specify the number of uses of a software element which indicate reuse,

And providing multiple choices for abstraction entities.