A preliminary testability model for object-oriented software

In software quality assurance, two approaches have been used to improve the effectiveness of fault detection. One attempts to find more efficient testing strategies; the other tries to use the design characteristics of the software itself to increase the probability of a fault revealing itself if it does exist. The latter which combines the best feature of fault prevention and fault detection, is also known as the testability approach to software quality assurance. This paper examines the factors that affect software testability in object-oriented software and proposes a preliminary framework for the evaluation of software testability metrics. The ultimate aim is to formulate a set of guidelines in object-oriented design to improve software quality by increasing their testability.