Question

Write a Java application to find the area of 1) rectangle 2) Triangle 3) Circle using runtime polymorphism concept. Shape Area rectangle length*width Triangle 0.5*length*width Circle PI*radius*radius.

I am confused as to what polymorphism is and would really appreciate some help. This is in Java as well.

Answer 1

input code:

output:

code:

import java.util.*;
/*make parent shape class*/
class Shape{
/*make one method*/
void Area()
{
System.out.println("Area of shape is this:");
}
}
/*make child class of shape so we can override method that is called runtime polymorsiphm*/
class rectangle extends Shape{
/*declare varibles*/
float width;
float length;
/*make constructor*/
rectangle(float w,float l)
{
width=w;
length=l;
}
/*override method*/
void Area()
{
System.out.println("Area of rectangle is :"+String.format ("%.2f", length*width));
}
}
/*make child class of shape */
class Traingle extends Shape{
/*declare varibles*/
float width;
float length;
/*make constructor*/
Traingle(float w,float l)
{
width=w;
length=l;
}
/*override method*/
void Area()
{
System.out.println("Area of Traingle is :"+String.format ("%.2f", 0.5*length*width));
}
}
/*make child class*/
class circle extends Shape{
/*declare varibles*/
float radius;
double PI=3.14;
/*make constructor*/
circle(float r)
{
radius=r;
}
/*override method*/
void Area()
{
System.out.println("Area of circle is :"+String.format ("%.2f", PI*radius*radius));
}
}
public class Main
{
   public static void main(String[] args)
   {
   /*make object of Shape class*/
       Shape[] elements={new rectangle(5,6),new Traingle(6,10),new circle(10)};
       /*call the method and print the area*/
       for(int i=0;i<elements.length;i++)
       {
       elements[i].Area();
       }
   }
}