VendingMachine.java

import java.util.*;
import java.io.*;

class InsufficientFundsException extends Exception {
    public InsufficientFundsException(String message){
        super(message);
    }
}

public class VendingMachine {
    private ArrayList<Item> list = new ArrayList<>();
    private Purse purse = new Purse();

    public VendingMachine(){
    }
    public VendingMachine(ArrayList<Double> allowedValues){
        purse = new Purse(allowedValues);
    }

    public Item get(int i){
        return list.get(i);
    }
    public int size(){
        return list.size();
    }

    public void sort(){
        Collections.sort(list);
        Collections.sort(purse.getCoins());
    }

    public void add(Item item){
        list.add(new Item(item));
    }
    public void add(int i, Item item){
        list.add(i, new Item(item));
    }
    public void del(int i){
        list.remove(i);
    }

    public Purse getPurse(){
        return purse;
    }
    public ArrayList<Double> getCoins(){
        return purse.getCoins();
    }

    void sell(int i) throws Exception {
        double price = get(i).getPrice();
        double balance = getPurse().getBalance();
        if(price <= balance){ // can sell
            this.del(i);
            getPurse().remove(price);
        } else { // cannot sell
            throw new InsufficientFundsException("Not enough money!");
        }


        //System.out.println(price + " " + balance);
    }
    /*
    public static void main(String args[]) {
        try {
            Item item1 = new Item("saldainis", 1.1);
            Item item2 = new Item("saldainis", 2.1);
            Item item3 = new Item("sultys", 3.1);

            VendingMachine vm = new VendingMachine();
            vm.add(item1);
            vm.add(item2);
            vm.add(item3);
            vm.del(1);
            vm.del(1);
            vm.add(item1);
            item1.setPrice(4.1);
            vm.add(item1);

            for(int i = 0; i < vm.size(); ++i){
                System.out.println(vm.get(i));
            }
        } catch(Exception e){
            System.out.println(e);
            System.out.println("Unexpected error, sorry!");
        }
    }
    */

}