Information Technology Reference
In-Depth Information
Chapter 2
Object-Oriented Concepts
Software engineering trends before the mid-1970s followed one basic programming
methodology, known as structured programming. The structured paradigm, also
called the classical paradigm, offered a very straight-forward approach to software
engineering which seemed sufficient for the time. This model provided a simple
view of a software product: the product was either operation oriented or data
oriented (Schach
2008
). In the first case, primary attention was paid to the functions
performed. In the second, the primary focus was on the information being handled.
The picture painted by the classical paradigm seemed uncomplicated in the begin-
ning, but as the field of software engineering grew, a fundamental flaw became
apparent. Describing a software application based exclusively on either the opera-
tions it was to perform or the data it was to manage was just too simplistic.
As solutions to the problem of oversimplification were being investigated,
brand new programming concepts began to emerge. The most influential of these,
and ultimately the most successful, is known today as the object-oriented
paradigm. In object-oriented programming, software is not broken down into
either operations or data, but rather into abstract software artifacts, called objects.
These objects are designed both to manage data and to carry out operations, thus
combining the two fundamentally related halves of a software product, which had
in the past been kept separate under the classical paradigm.
To better explain this concept, we turn to a real world example: a human being.
In the classical model, specific actions and physical characteristics were kept
separate from one and other. For example a person's name, eyes, birth date, hands,
and taste in music would be separated from the actions he or she is able to perform
like, holding a conversation, winking at a friend, having a birthday party, listening
to a CD, or shaking an acquaintance's hand. If we apply the object-oriented
paradigm however, all of these attributes and actions are combined to make up a
single unified object: a human being. This object is able to use its attributes, which
are stored internally, to perform actions, and thus can be thought of as a well-
defined, independent entity rather than an over encumbering conglomeration of
functions and data.
