OOP Concepts In Java

OOP concepts in Java are the main ideas behind Java's Object Oriented Programming. They are:

Object

Any entity that has state and behavior is known as an object. It can be either physical or logical.

For example: chair, pen, table, keyboard, bike etc.

Class & Instance

Collection of objects of the same kind is called class. It is a logical entity.

Abstraction

Abstraction refers to the quality of dealing with ideas rather than events. It basically deals with hiding the details and showing the essential things to the user.

Abstract class: Abstract class in Java contains the 'abstract' keyword. If a class is declared abstract, it cannot be instantiated.

Interface: Interface in Java is a collection of abstract methods and static constants. In an interface, each method is public and abstract but it does not contain any constructor. Along with abstraction, interface also helps to achieve multiple inheritance in Java.

Encapsulation

Binding (or wrapping) code and data together into a single unit is known as encapsulation. It means to hide our data in order to make it safe from any modification.

Inheritance

create new classes that share some of the attributes of existing classes.For eg, a child inherits the properties from his father.

Similarly, in Java, there are two classes:

1. Parent class (Super or Base class)

2. Child class (Subclass or Derived class)

A class which inherits the properties is known as 'Child class' whereas a class whose properties are inherited is known as 'Parent class'.

Inheritance is classified into 4 types:

Single Inheritance

It enables a derived class to inherit the properties and behavior from a single parent class.

Here, Class A is a parent class and Class B is a child class which inherits the properties and behavior of the parent class.

Sign up now to get the most out of Books2Read

Discover something great at Books2Read.

Thanks for signing up for Books2Read notifications!