OOPS concepts in Java.

Java Programming Java8Object Oriented Programming

The Object Oriented programming paradigm plays an important role in human-computer interface. It has different components that take real world objects and perform actions on them, making live interactions between man and the machine. Following are the components of OOPS −

  • This paradigm describes a real-life system where interactions are among real objects.

  • It models applications as a group of related objects that interact with each other.

  • The programming entity is modeled as a class that signifies the collection of related real-world objects.

  • Programming starts with the concept of real-world objects and classes.

  • The application is divided into numerous packages.

  • A package is a collection of classes.

  • A class is an encapsulated group of similar real-world objects.


Real-world objects share two characteristics − They all have state and behavior. Let us see the following pictorial example to understand Objects.

In the above diagram, the object ‘Dog’has both state and behavior.

An object stores its information in attributes and discloses its behavior through methods. Let us now discuss in brief the different components of object oriented programming.

Data Encapsulation

Hiding the implementation details of the class from the user through an object’s methods is known as data encapsulation. In object oriented programming, it binds the code and the data together and keeps them safe from outside interference.

Public Interface

The point where the software entities interact with each other either in a single computer or in a network is known as a public interface. This help in data security. Other objects can change the state of an object in an interaction by using only those methods that are exposed to the outer world through a public interface.


A class is a group of objects that have mutual methods. It can be considered as the blueprint using which objects are created.

Classes being passive do not communicate with each other but are used to instantiate objects that interact with each other.


Inheritance as in general terms is the process of acquiring properties. In OOP one object inherits the properties of another object.


Polymorphism is the process of using same method name by multiple classes and redefines methods for the derived classes.


Published on 23-Apr-2018 11:47:53