Chapter 6 Conventional method support for managing changes during maintenance and evolution

In this Chapter, we further highlight the difficulties to combat the problems of change with conventional techniques, in view of maintenance and evolution challenges discussed in Chapter 1. We also briefly preview some of the remedies to fight these problems using unconventional approaches. With emphasis on complexity inherent in software, we focus on the following problems: Poor visibility of past changes triggers much re-work that could be avoided should the knowledge of the past changes be available to developers. Each new change is re-invented afresh and implemented in its own way, despite possible similarities to past changes. By ignoring similarity of evolution patterns, we reinvent the way changes must be implemented, redoing the same kind of costly change impact analysis all over again. We blow up code size and complexity. The number of similar component versions explodes, degrading conceptual integrity of the program design. The overall complexity of an evolving program grows, making any future changes even harder.