This document discusses object-oriented programming concepts. It aims to explain the fundamentals of OOP including classes, objects, and the four main OOP concepts: inheritance, abstraction, encapsulation, and polymorphism. The key OOP concepts are defined as inheritance allowing a class to inherit properties from another class, encapsulation hiding implementation details and only exposing a public interface, and abstraction and polymorphism allowing classes to take multiple forms. Examples are provided to illustrate classes, objects, and each of the OOP concepts.

1. Object Oriented
Programming

2. Learning Outcome
● On successful completion of this module,
○ Explain the fundamentals of Object-Oriented Programming concepts
○ Design Object-Oriented based applications
○ Develop Object-Oriented applications

3. Lesson -1 : fundamentals of Object-Oriented
Programming

4. Toady’s Aim
● Explain the fundamentals of Object-Oriented Programming
○ Understand and describe OOP
○ Understand and describe OOP concepts
■ Inheritance
■ Aptraction
■ Encapsulation
■ Polymorphism

5. Good Programming
● more code not necessarily a good thing
● measure good programmers by the amount of functionality
● code can be used many times but only has to be debugged once!
● Code should be
○ often self-contained
○ used to break up code
○ intended to be reusable
○ keep code organized
○ keep code coherent

7. Problem to Solution

9. Object:
● A specific real world entity
● Objects have all the attributes specified in the class definition
● An object is an instance of a concept
○ 1234 is an instance of an int
○ "hello" is an instance of a string

10. Class:
● Specifies the characteristics of an entity but is not an instance of that entity
● A class is a blueprint or template that defines the structure of the object.

11. Format:
public class <name of class>
{
attributes
methods
}
Example:
public class Employee {
private int name; // Attribute - stores the name of the employee
public void sayName() // Method - prints the name of the employee
{
System.out.println("My name is " + name);
}
}

12. Activity: What is the value of X?
public class Calculator{
int x = 10;
public static void main(String[] args) {
Calculator myObj = new Calculator();
myObj.x = 25; // x is now 25
System.out.println(myObj.x);
}
}
Attributes
Method
Object

13. ○ Inheritance
○ Abstraction
○ Encapsulation
○ Polymorphism
What are the Concepts in OOP?

14. Inheritance
● Inheritance is a fundamental concept in object-oriented programming (OOP)
that allows a class to inherit properties and behaviors from another class.
● Inheritance represents the IS-A relationship which is also known as a parent-
child relationship
● It enables code reuse and promotes the organization and hierarchy of classes.
○ Sub Class/Child Class: Subclass is a class which inherits the other class. It is also called a
derived class, extended class, or child class.
○ Super Class/Parent Class: Superclass is the class from where a subclass inherits the features. It
is also called a base class or a parent class.

15. Real world example of inheritance

16. Example of inheritance
class Employee{
float salary=80000;
}
class Programmer extends Employee{
int bonus=30000;
public static void main(String args[]){
Programmer p=new Programmer();
System.out.println("Programmer salary is:"+p.salary);
System.out.println("Bonus of Programmer is:"+p.bonus);
}
}

17. Activity
● Identify the differences between all 5 types of the inheritance ?
● Find the examples for each type of inheritance?

18. Types of the inheritance

19. Encapsulation
● "sensitive" data is hidden from users
● way of hiding the implementation details of a class from outside access and
only exposing a public interface that can be used to interact with the class.
● encapsulation is achieved by declaring the instance variables of a class as
private,

20. class Person {
private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) { this.age = age; }
}
public class Display{
public static void main(String[] args)
{
Person person = new Person();
person.setName("John");
person.setAge(30);
System.out.println("Name: " + person.getName());
System.out.println("Age: " + person.getAge());
}
}

21. Activity
● Find the Access Modifier?

22. Are we achieved our aim?
○ Understand, identify and describe Classes, Objects, Properties and Methods
○ Understand and describe OOP concepts
■ Inheritance
■ Encapulation

23. Reference