Designing Debugging Models for Object Oriented Systems

Bugs are inevitable in any software development life cycle. Most bugs are detected and removed in the testing phase. In software, we can classify bugs into two categories: (1) bugs of different severity (2) bugs of different complexity. Prior knowledge of bug distribution of different complexity in software can help project managers in allocating testing resources and tools. Various researchers have proposed models for determining the proportion of bugs present in software of different complexity but none of these models have been applied to object oriented software. Software reliability growth models have been used during later stages of testing to predict the number of latent bugs dormant in the software. Once a bug is found in the software, efforts have been made by the development team to debug it. It is found in practice that debugging may not be perfect and during removal of bugs, some new bugs may be generated and this phenomenon is called imperfect debugging. In this paper, we have developed a software reliability growth model for object oriented software system for perfect debugging in which new bugs are not generated during removal process and also by incorporating imperfect debugging, where new bugs are generated during removal process in a proportion removed bugs. Here, the proposed paper is used to assess the reliability growth of object oriented software developed under concurrent distributed development environment. We have collected bug reported data of MySQL for python. Numerical illustration has been also presented in the paper.