Object Oriented Software Concepts

Advanced Diploma in IT Systems Analysis and Design
Question 1.
a. Object oriented software concepts.
In 2016, Satzinger, Jackson and Burd, suggested that when developing object oriented
software abstraction, Encapsulation, inheritance and polymorphism concept are so
important to implement in those objects.
Abstraction.
Abstraction: Data is represented and how it is implemented is it is kept out of sight.
There two main type of abstraction of data which are datatypes and object abstracts.
Encapsulation.
When interface is made available to users but purpose how it’s inside operation is hidden from
access.
Encapsulation is keeping implementation of data by preventing their accessing and mutating.
Inheritance hierarchy.
Modeling objects with features which are related. For example vehicle most vehicle has same
main features example all vehicles have wheels, engine and steer. For this redundancy avoidance
is to bring concept of inheritance. Inheritance it is reusing code of a super type by subtype object
objects.
Modularity.
It is about logical and physical appearance of objects.
Self-Contained : "Agile & Autonomous".
It means a system is made up of small components. This small components helps in functioning
and performance of system. You cannot change any small component the system may fail to
function. So modification have to be done to whole system.
High cohesion and loos coupling is encouraged in modulation.
Polymorphism.
It is self-representation in different form with same naming and operation is different.
Polymorphism requires inheritance.
Object-oriented polymorphism means operating not in same method, depends on instances
being operated on. Polymorphism enhances internal arrangement of objects to be similar with
external interface.

b. Object oriented concepts facilitate the design, testing and maintenance of software
systems.
Design
Object oriented support inheritance where objects are reused. The aim of reusability of software
is to make production of software low by substituting development with recycle. Reuse is to
reduce the cost of software production by replacing creation.
When design system high cohesion is allowed and low coupling is discouraged.
Attributes which public are overridden and inheritance take place so the percentage of them is
important. Immutable attributes its percentage is note. When percentage of immutable attribute is
high it means they conform to encapsulation.
Testing.
Modularity is allow during testing software need to divide and conquer principle during
testing .Dived testable modules into small manageable tasks
Changes in operation of software;
Maintenance.
Faults are always repaired when there is failure.
Upgrade of hardware and software;
System reliability and performance is improved always
New software requirements keep coming in place while software is in use.
Question 2.
In 2016, Lethbridge and Laganiere explained that Uml class diagrams make work of programmer
easy because it indicate methods and attributes used on class.

Figure 1 below showing Class diagram of Domain system.