OOPs concept

Definition of OOPs Concepts in Java

The main reason behind Java’s Object Oriented Programming is the concept of OOPs. They are an inheritance, abstraction, encapsulation, and polymorphism. You can understand the working of Java by getting to know about the above terms. It is fully safe and secured and creates working methods and variables and is reusable.

List of OOPs Concepts in Java

Here are four main OOPs concepts in Java. They are:


Complexity is represented in a simple way by means of Abstraction. There are some simple things like classes, objects, and variables for representing more complex code and data in Java.


Fields are kept inside a class private then access is provided to them with the help of public methods. For keeping the data and code safe inside the class, it is a secured barrier and this is the way for re-using objects like variables or components without permitting open access globally.

Why Java Doesn’t Support Multiple Inheritance


This is an important feature of Object Oriented Programming in Java and new classes are created by the programmers for sharing few attributes of present classes.


The same word can be used by the programmers in JAVA OOPS concept and it has different meanings in different contexts. In Java, one form of polymorphism is method overloading. Here is where different meanings are implied by the code itself. Method overriding is another form. Here is where the values of the supplied variables imply different meanings.

How OOPs Concepts in Java Work

The components are created by the programmers and it can be reused in various ways but still, it will remain secured and the si the working of OOPs concept in Java.

How Abstraction Works

Useful, reusable tools are created by programmers with the concept of abstraction in Java. There are several ways in which an object can be created by the programmer. Data structures, variables, functions are few ways. Different classes of objects can also be created by the programmers. For defining the objects these are ways.

A class of variable might be an address for specifying each address object that has street, name, city and zip code.

Top 13 Oops Java Interview Questions

How Encapsulation Works

Without comprising the security, you can re-use the code with the help of encapsulation. It saves a lot of time and is a wonderful tool for OOPs concept. For instance, a piece of code may be created for calling specific data from a database. For reusing the code with other processes or databases it may be useful. Our original data is kept private at the same time it can be changed without breaking it for others who chose it in the meantime.

How Inheritance Works

There is another easy going Java OOPs concept called Inheritance and it works by one class using the properties of the other. The subclass is called as the inheriting class or a child class. The class from which it inherits is called the parent class. If a new class inherits the properties from an old class the extends keyword is used.

How Polymorphism Works

With the help of a reference to the parent class, the working of Polymorphism in Java happens and this affects the child class object. If you are creating a class called parrot by extending the bird class and this class might implement bird show class. Here the parrot class becomes polymorphic as it inherits the attributes of both the bird show class and the bird class.

What is Polymorphism in Java?

Single Responsibility: This is the best practice in Java and in the layman context it can be said that a class should have only one functionality. Thus it can be invoked on its own without any difficulty due to coupling.

Open Closed Design: All the methods and classes can be made which is closed for modification but is open for extension The code which is tried and tested can remain static and can be modified for doing new tasks as per the requirement.