Dynamic polymorphism in java with example program

• Polymorphism means defining multiple methods with same name.


• Two types of polymorphism
  1.Static polymorphism
  2.Dynamic polymorphism.

Static polymorphism:

• Defining multiple methods with same name and with different type of arguments is known as static polymorphism.
• We can achieve this static polymorphism using method overloading.

Static polymorphism in java with example program

1. package com.instanceofjava;
2. class A{
3.  
4. public void show(int a){
5. System.out.println("saidesh");
6. }
7.  
8. public void show(int a,int b){
9. System.out.println("ajay");
10. }
11.  
12. public void show(float a){
13. System.out.println("vinod");
14. }
15. public static void main(String args[]){
16.  
17. A a=new A();
18.  
19. a.show(10);
20. a.show(1,2);
21. a.show(1.2);
22.  
23. }
24. }

Output:

1. saidesh
2. ajay
3. vinod

Dynamic polymorphism:

• Defining multiple methods with same name and with same signature in super class and sub class.
• We can achieve dynamic polymorphism by using method overriding concept in java.
• Define a method in super class and override same method with same signature in sub class
• Whenever we call the method on t the object based on the object corresponding class method will be executed dynamically.

Java example program on dynamic polymorphism: (Real time example)

1. package MethodOverridingExamplePrograms;
2. public class Vehicle{
3.  
4. void Start(){ 
5. System.out.println("Vehicle started")
6. }
7. 
   
8. }

1. package MethodOverridingExamplePrograms;
2. public class Car extends Vehicle{
3.  
4. void Start(){ 
5. System.out.println("Car started")
6. }
7. 
   
8. }

1. package MethodOverridingExamplePrograms;
2. public class Bus extends Vehicle{
3.  
4. void Start(){ 
5. System.out.println("Bus started")
6. }
7. 
   
8. }

1. package MethodOverridingExamplePrograms;
2. public class Bike extends Vehicle{
3.  
4. void Start(){ 
5. System.out.println("Bike started")
6. }
7. 
   
8. }

1. package MethodOverridingExamplePrograms;
2. public class Test{
3.  
4. public static void startVehicle(Vehicle vh){ 
5.    
6. vh.start();
7. 
   
8. 
   
9.  
10. }
11. 
    
12. }

•  In the above example based on the object creation at run time corresponding class method will be executed.