Question

Can someone please create a payment java class that can read bills and coins for a vending machine and is not hardcoded and you can get the price from the objects.

Thank you.

Answer 1

import java.util.InputMismatchException;
import java.util.Scanner;

public class VendingMachine {

public static void main(String[] args) {

     Scanner scn = new Scanner(System.in);

     // Use an array Object if you have a list of items.
     double[] itemPrices = {1.25, .75, .90, .75, 1.50, .75};

     // This array starts from 0 end ends at 5. SO, we have only 5 item costs only.
     int maxItem = itemPrices.length;

     // Have we been given an item that is Ok yet?
     boolean itemFound = false;

     // We have not been provided an item # yet. This will have to be non-null
     Integer item = null;

     // read an item number until an existing item is found.
     do {
         System.out.print("Enter an item number: ");
         try {
             item = scn.nextInt();
             if ( item >= 1 && item <= maxItem ) {
                 itemFound = true;
             } else {
                 // Inform the user of the problem. Give them another chance.
                 // String.format is very neat stuff. Use it.
                 String message = String.format("Unfortunately, item #%d does not exist.", item);
                 System.out.println(message);
             }

         // note how an exception is raised when we get an invalid input.
         // you must consider what happens when the input is invalid.
         } catch (InputMismatchException e) {
             System.out.println("Bad input. Try again.");
             scn.next();
         }
     } while (!itemFound);

     Double paid = null;
     do {
         System.out.print("Enter the amount to be paid: ");
         try {
             paid = scn.nextDouble();
         } catch (InputMismatchException e) {
             System.out.println("Bad input.Please Try again.!!!!");
             scn.next();
         }
     } while (paid == null);

     double valueOfItem = itemPrices[item-1];

     double changeMoney = paid - valueOfItem;

     double moneyNeeded = 0 - changeMoney;

     if ( moneyNeeded > 0 ) {
         // We can inform the user what the problem was. And again the String.format magic.
         String message = String.format("Please insert another $%.2f.%n", moneyNeeded);
         System.out.println(message);

         // But this time, we will gracefully exit.
         System.exit(0);
     }

     String message = String.format("Thank you for buying item #%d, your changeMoney is $%.2f. Please come again!", item, changeMoney);

     System.out.println(message);

}

}