When to use abstract class and interface

In this tutorial, we have discussed abstraction in Java in detail. Abstraction is a technique of hiding unnecessary details from the user. The user is only given access to the details that are relevant. Vehicle operations or ATM operations are classic examples of abstractions in the real world.

Abstraction in the real world Making coffee with a coffee machine is a good example of abstraction. You need to know how to use your coffee machine to make coffee. You need to provide water and coffee beans, switch it on and select the kind of coffee you want to get.

Abstraction means displaying only essential information and hiding the details . Data abstraction refers to providing only essential information about the data to the outside world, hiding the background details or implementation. Consider a real life example of a man driving a car.

The purpose of an abstract class is to provide a blueprint for derived classes and set some rules what the derived classes must implement when they inherit an abstract class . We can use an abstract class as a base class and all derived classes must implement abstract definitions.