Software Objects and RealWorld Representations - Programming GPS and OpenStreetMap Applications with Java - page 11

This topic is about objects, things in the real world and since science
describes the real world to a very high level of detail it would be a shame
not to make use of this knowledge|available online. By \lling" indepen-
dent objects with scientific facts, they become more real with every new
fact added. One can even consider the idea of providing common classes
implementing scientific knowledge to be used in any context.

1.4 Models in Physics

Object entities abstract internal processing from the external application
logic to simplify the modeling of business logic, rules or algorithms that
handle the exchange of information between a database and user interface.
The object-oriented approach adds semantics to programming languages
and as such, computer language, mathematical language, and human lan-
guage might be considered to have moved closer together. 2

JavaWhitePaper>Chapter3>JavaisObjectOriented

. . . object technology is a collection of analysis, design,
and programming methodologies that focuses design onmod-
elingcharacteristics and behavior ofobjectsin therealworld
. . . objects are software programming models. In your every-
day life, youre surrounded by objects: cars, coffee machines,
ducks, trees. . . .
An objects behavior is defined by its methods. . . you can
build entire networks and webs of objects that pass messages
between them to change state. This programming technique
is one of the best ways to create models and simulations of
complexreal-worldsystems.

Nevertheless, modeling was not an invention of the software industry. In
this chapter, we have looked at electrical devices and cars represented as
individual software entities. Since software, devices, and machines are man-
made constructs, these analogies might raise the impression that modeling
is restricted to engineering. Creating a device and representing the plan
in a software language can be part of one process. This section is meant
to point out that modeling has evolved from reverse engineering the world.
For centuries physicists have created their model of the world. Modeling
of real-world objects goes way beyond controlling electrical devices. From
a scientific point of view, everything (matter) is composed of a sizeable
number of elements and held together by only four forces.

2 You can find theJavaWhitePaperonline at java.sun.com/docs/white/langenv/ .