Declaring a method in sub class which is already present in parent class is known as method overriding.
Overriding is done so that a child class can give its own implementation to a method which is already provided by the parent class. In this case the method in parent class is called overridden method and the method in child class is called overriding method. In this guide, we will see what is method overriding in Java and why we use it.
Lets take a simple example to understand this. We have two classes: A child class Boy and a parent class Human. The Boy class extends Human class. Both the classes have a common method void eat(). Boy class is giving its own implementation to the eat() method or in other words it is overriding the eat() method.
The purpose of Method Overriding is clear here. Child class wants to give its own implementation so that when it calls this method, it prints Boy is eating instead of Human is eating.
class Human{
//Overridden method
public void eat()
{
System.out.println("Human is eating");
}
}
class Boy extends Human{
//Overriding method
public void eat(){
System.out.println("Boy is eating");
}
public static void main( String args[]) {
Boy obj = new Boy();
//This will call the child class version of eat()
obj.eat();
}
}
Output:
Boy is eating
Advantage of method overriding:
▪︎The main advantage of method overriding is that the class can give its own specific implementation to a inherited method without even modifying the parent class code.
▪︎This is helpful when a class has several child classes, so if a child class needs to use the parent class method, it can use it and the other classes that want to have different implementation can use overriding feature to make changes without touching the parent class code.
