Difference Between Static And Dynamic Polymorphism?

Compile time Polymorphism

The Polymorphism which occurs at compile time is called Compile time Polymorphism

Compile time polymorphism is called as static polymorphism or static binding or early binding

It provides fast execution because occurs at compile time

Example: Method overloading (Same method name and different parameter)

class Cal

{

    void add(int a, int b)

    {

         System.out.println("sum of two number:"+(a+b));

    }

    void  add(int a, int b, int c) 

    {

          System.out.println("sum of three number:"+(a+b+c));

    }

}

public class LearningPoint92

{

   public static void main(String args[])

   {

                Cal c1 = new  Cal();

                 c1.add(50, 20);

                 c1.add(50, 20, 30);

              }

        }

OUTPUT:

sum of two number:70

sum of three number:100

Runtime time Polymorphism

The Polymorphism which occurs at run time is called Run time Polymorphism

Run time polymorphism is called as dynamic polymorphism or dynamic method dispatch or dynamic binding or late binding

It provides slow execution because occurs at run time

Example: Method overriding (Same method name and same parameter)

.

class A{

   public void show(){

            System.out.println("Hello");

   }

}

public class B extends A{

        public void show(){

       //   super.show();   //to call superclass method

            System.out.println(" Welcome To LearningPoint92");

   }

   public static void main(String args[]){

            A a1 = new B();

            a1.show();

      }

     }

OUTPUT:

Welcome To LearningPoint92

Note:

upcasting is required in runtime polymorphism. Super class reference refer to subclass object is called upcasting.you can call subclass method using upcasting

A a1 = new B();

Where  A  a1=superclass reference

Where new B () =subclass reference