What is Super keyword
It is a reference variable which always refers to the immediate parent class object. It performs following operations:
1. Used to call the immediate parent class constructor.
e.g.
class Fruit{
Fruit(){
System.out.println(“Fruit class created”);
}
}
class Apple extends Fruit{
Apple () {
super();//It will call parent class constructor
System.out.println(“Apple class created”);
}
public static void main(String args[]){
Apple a=new Apple ();
}
}
Output
Fruit class created
Apple class created
2. Refer immediate parent class instance variable
e.g.
class Fruit{
int quantity=20;
}
public class Apple extends Fruit{
int quantity=10;
void show(){
System.out.println(super.quantity);/*It will print Fruit’s quantity that is Refer immediate parent class instance variable */
System.out.println(quantity);
}
public static void main(String args[]){
Apple ap=new Apple ();
ap.show();
}
}
Output
20
10
3. Can call immediate parent class method
e.g.
class Fruit{
void print(){
System.out.println("Fruit class created");}
}
public class Apple extends Fruit{
void print(){
System.out.println("Apple class created");
}
void show(){
super.print();// It will call parent class method
print(); // It will call apple class method
}
public static void main(String args[]){
Apple ap = new Apple();
ap.show();
}
}
Output
Fruit class created
Apple class created
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