//TwoCatchesDemo.java

import java.util.Scanner;

public class TwoCatchesDemo
{
    public static void main(String[] args)
    {
        try
        {
            System.out.println("Enter number of widgets produced:");
            Scanner keyboard = new Scanner(System.in);
            int widgets = keyboard.nextInt();
            if (widgets < 0)
                throw new NegativeNumberException("widgets");

            System.out.println("How many were defective?");
            int defective = keyboard.nextInt();
            if (defective < 0)
                throw new NegativeNumberException("defective widgets");

            double ratio = exceptionalDivision(widgets, defective);
            System.out.println("One in every  " + ratio
                + " widgets is defective.");
        }
        catch (DivideByZeroException e)
        {
            System.out.println("Congratulations! A perfect record!");
        }
        catch (NegativeNumberException e)
        {
            System.out.println("Cannot have a negative number of "
                + e.getMessage());
        }
        System.out.println("End of program.");
    }

    public static double exceptionalDivision
    (
        double numerator,
        double denominator
    ) throws DivideByZeroException
    {
        if (denominator == 0)
            throw new DivideByZeroException();
        return numerator / denominator;
    }
}