Zeek_84_ThrowVSThrows.java

 

/*

 throw and throws is the concept of Exception Handling.

 

 throw -->  throw keyword throw the exception explicitly from a method or a block of code.

            (Usually inside try block)

       -->   throw is used within the method.

 

 throws-->  throws keyword is used in the method signature to declare an exception which might be

            thrown (by the function) while the execution of the code.

       -->  throws is used with the method signature.

 

 

--> Write a code to Calculate area of a circle of radius r

--> Take radius(r) as an input from user

--> Create a Custom  Exception class that  gives exception for Negative Radius

--> Use throw and throws keywords.

 */

package com.company;

import java.util.Scanner;

class NegativeRadiusException extends Exception{

    public String toString() {

        return "Radius of circle cannot be negative";

    }

}

class Area {

    public static void AreaCircle() {

       

        Scanner sc=new Scanner(System.in);

       

        System.out.println("Enter Radius:");

        int r=sc.nextInt();

       

   if (r<0) {

            try {

                throw new NegativeRadiusException();

            }

           

            catch(Exception e){

                System.out.println(e.toString());  

                e.printStackTrace();

            }

    }

    else {  

          double Area= Math.PI* r*r;

          System.out.println("Area of Circle: "+Area);  

    }

    }

}

public class Zeek_84_ThrowVSThrows {

    public static void main(String[] args) throws NegativeRadiusException {

        Area x= new Area();

        x.AreaCircle();

    }

}