Java Program to Demonstrate Abstract Class

OOPs

Java Program to Demonstrate Abstract Class

A Java program to demonstrate the usage of abstract classes and methods.

Problem Description

Write a Java program to demonstrate the concept of abstract classes and abstract methods.

Code

AbstractClass.java

abstract class Animal {
    abstract void makeSound();

    public void eat() {
        System.out.println("I can eat.");
    }
}

class Dog extends Animal {
    public void makeSound() {
        System.out.println("Bark bark");
    }
}

public class AbstractClass {
    public static void main(String[] args) {
        Dog d1 = new Dog();
        d1.makeSound();
        d1.eat();
    }
}

Output

Bark bark
I can eat.

Explanation

abstract Class: Cannot be instantiated. Can contain both abstract and non-abstract methods.
abstract Method: Has no body. Must be implemented by the subclass.

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