TABLE OF CONTENTS This section of the book aims to overview the means by which software is changed in practice.
The actual process of making a change is a complex business and even the simplest changes go through defined stages as they are brought about. Essentially, the following steps will be carried out:
The maintenance programmer gains an understanding of the current system and the context within which it operates.
The change is carried out
The new version is tested and then goes live.
The above steps involve significant software engineering and programming skills, but one very important stage has been omitted that of initially identifying and agreeing the need for change. This, though requiring an appreciation of software engineering, is a managerial decision, based on knowledge of the overall context within which the proposed change is to be made. The first stage above, that of understanding the current system, affects management decisions on software change and the means by which that change is carried out. Thus,
the identification of the need for change and agreement to its being carried out
is also a stage in the process.
Each of the above steps covers significant effort within the maintenance lifecycle. This section of the book looks in detail at these stages.
Understanding is a vital precursor to implementing change. Without an understanding of what the...
