Principles of Object-Orientation in IOS

Principles of Object-Orientation

 

The concepts and core mechanisms of object-orientation are the building
blocks of an OO app. In this section, you find out how to apply those concepts
and techniques to create well-designed, easy-to-understand programs.
Separation of concerns is a design principle that calls for breaking your system
(or program) into components, each of which either implements a certain
piece of functionality, such as heating water (in the tea-making example) or
encapsulates a nonfunctional quality such as performance.
Separation of concerns starts early in OO development, right at the time
objects are identified and their classes are defined. Each class represents a
concern, such as a Vessel, a Stove, or a Faucet. The domain naturally identifies
these concerns for you.
The benefit of separating concerns is twofold:
? It reduces the complexity of developing the software by allowing development
of the software in pieces.
? It allows independent evolution and maintenance of the system.
In order for independent evolution to happen, the system must be partitioned
so that the components exhibit low coupling and high cohesion.