SOFTWARE DESIGN METHODS AND REPRESENTATIONS - Software Design for Six-Sigma: A Roadmap for Excellence - page 86

TABLE 4.2 Software Design Methods Analysis

Type of Design
Method

Anticipation of
Change Modularity Generality Consistency

Object-Oriented Excellent Excellent Excellent Excellent

Level-Oriented
Design

Excellent Average to poor

(see top-down
design)

Average to Poor
(see top-down
design)

Good

Data Flow or
Structured
Design

Excellent Poor Poor Good

Data-Structure
Oriented
Design

Good Excellent Excellent Good

the time that a user takes to become familiar with the software. If a user learns the
basic elements of dealing with an interface, they do not have to be relearned each
time for a different software application. 20
Table 4.2 illustrates each software design method and comments on the four
factors of modularity, anticipation of change, generality, and consistency. The scale
of excellent, good, average or no comment, and poor were used to compare and
contrast the different software techniques and how they compare with one another.
Based on the results of this study, it seems that object-oriented design may be
the best software design method, at least for some types of applications. Indeed,
object-oriented programming is one of the most widely used and easiest to learn
approaches. First of all, object-oriented methods are very modular, as they use black
boxes known as objects that contain code. Next, one of the main benefits of using
object-oriented software is that it can be reused with relative ease. Object-oriented
software also includes polymorphism, which is the ability to assign different meanings
to something in different contexts and allows an entity such as a variable, a function,
or an object to have more than one form. Finally, tools such as design patterns and
the UML make object-oriented programming user friendly and easy to use. In fact,
proponents of object-oriented design argue that this type of programming is the easiest
to learn and use, especially for those who are relatively inexperienced in computer
programming. This is because the objects are self-contained, easily identified, and
simple. However, object-oriented programming has a few drawbacks that should be
noted as well. Specifically, object-oriented design takes more memory and can be
slow.
Probably the next best software design method that can be used is data-structure-
oriented design. Data-structure-oriented design tends to have high modularity. In
fact, some types of Jackson Development Method programs can be said to be object-
oriented. Data-structure-oriented design also has a high level of anticipation of change

20 http://www.d.umn.edu/

∼ gshute/softeng/principles.html.