Category Archives: OO Analysis and Design

Java serious OOP Practice

Problem statement: Write a program to simulate a car dealership sales process. We will have employees, working selling vehicles to customers.

you have to think about nouns(a person, name or thing) while doing OOP, we have 4 nouns in the problem statement.

if false in purchaseCar()

if true in purchaseCar()





Interface, Abstract Class and Polymorphism Example class





My Java OOP example from Lessons


My Beautiful Crafted Java OOP


Design Pattern and Object oriented Data Analaysis

Writing here to clearing engineering concept of a software for future reference.

Example for Class, Constructors and Methods:

Interface Example




What is this keyword in OOP

What is “this”?

You may have noticed something slightly strange in our methods. Look at this one for example:

You are probably wondering what “this” is. The this keyword refers to the current object the code is being written inside — so in this case this is equivalent to person.

JavaScript OOP Paradigm Clear


OOP concept clearings from some MOOC courses





Some Resources(Books, Links) for OOAD

Polymorphism: Method Overloading and Method Overriding and Method Hiding

Method Overriding:

another good exmple:

this video is good for learning overriding:

Method Hiding:


OOP Topics Need To Cover

OOP Topics Need To Cover

OOP Topics Need To Cover

SOLID Concepts

Object Oriented Programming Concepts