Software Library Investment Metrics: a New Approach, Issues and Recommendations

Software quality is considered as one of the most highly interacting aspects in software engineering. It has many dimensions that vary depending on the users' requirements and their points of view. Thus, the varying dimensions lead to complications in measuring and defining the software quality appropriately. The use of libraries increases software quality more than using generic programming as these libraries are prepared and tested in advance. Moreover, these libraries reduce the effort spent in the designing, testing and the maintaining processes. In this research, a new model is introduced to calculate the saved effort that results from using libraries instead of generic programming in testing, coding, and productivity processes. The proposed model consists of three metrics. These metrics are the library investment ratio, the library investment level, and program simplicity. An experimental analysis has been done onto ten software products to compare the outcomes of the model with reuse percent. The outcomes show that the model gives better results than reuse percent, because the model is deepening in the source code more than the reuse percent does. Also, the model has a better effect on the improvement of software quality and productivity, rather than reuse percent.