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Super Keyword in java

Super Keyword in java:-
The parent class is also called Superclass in Java and this method is used to access the parent class method.
using this we can call the parent class method from the child class method.
Super is also used in the constructor to call parent class constructor to child class constructor.
Example of Super Keyword in java:-
public class A {
    int a=2;
     void fun()
    {
        System.out.println("A");
    }
}
public class B extends A {
         void fun1()
    {
        super.fun();
    }
}
Another Example of Super Keyword in Java With Overring:-

class ExamSystem
{
    ExamSystem()
    {
     System.out.println("Default Constructor");
    }  
    ExamSystem(String s)
    {
         this();
        System.out.println("Constructor"+s);
           }
    void examDuration()
    {
       System.out.println("3 hours");
    }

    void examContent()
    {
        System.out.println("Exam Content");
    }
    void examPattern() 
    {
        System.out.println("Number System");
    }
}
class ExamSystemNew extends ExamSystem
{
    ExamSystemNew()
    {
        super("super");
        System.out.println("Exam System New Constructor");
    }
    void examPattern() 
    {
        super.examPattern();
        System.out.println("Grade System");
    }
   public static void main(String args[])
   {
       //ExamSystemNew obj = new ExamSystemNew();
      ExamSystem obj = new ExamSystemNew();
     //   ExamSystemNew obj = new ExamSystem();
       obj.examDuration();
       obj.examPattern();
       obj.examContent();
   } 
}
Another Example of Super Keyword with overriding:-
package calc;
public class Billing {
String item;
int qty;
float price;
double total;
void accept(String item,int qty,float price)
{
this.item =item;
this.qty=qty;
this.price=price;
}
    void bill()
    { 
     total = price*qty;
    
    }
    void displayBill()
    {
    System.out.println("Total bill is "+total);
    }
}
package calc;
public class BillingNext extends Billing {
void bill()
    { 
super.bill();
super.displayBill();
     total = (price*qty);
     total = total+(total*.18F);
    
    }
public static void main(String[] args) {
BillingNext obj = new BillingNext();
obj.accept("Keyboard",3,150.0F);
obj.bill();
obj.displayBill();
}
}

Super Keyword Example using constructor and three different classes A, B, and C:-
public class A {
A()
{
System.out.println("A Class Constructor");
}
   void fun()
   {
   System.out.println("A");
   }
}
public class B extends A {
B()
{
super();
System.out.println("B Class Constructor");
}
void fun2()
{
super.fun();
System.out.println("B");
}
}
package staff;
public class C extends B{
void fun3()
{
super.fun();
System.out.println("C");
}
}
package staff;
public class BMain {
public static void main(String args[])
{
C obj = new C();
obj.fun3();
}
}

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