MealCard.java

public class MealCard {

    private final static int DEFAULT_BALANCE = 1000;
    private int points;
    protected static int numberOfCards = 0;

    public MealCard(int points) {
        this();
        this.points = points;
    }

    public MealCard() {
        this.points = DEFAULT_BALANCE;
        numberOfCards++;
    }

    public int getPoints() {
        return DEFAULT_BALANCE + points;
    }

    public void setPoints(int points) {
        this.points = Math.max(points,0);
    }

    public void purchasePoints(int points) {
        this.points += Math.max(points, 0);
    }

    public void purchaseItem(int foodPoints) {
        if (getPoints() > foodPoints) {
            this.points = getPoints()- foodPoints;
        } else {
            System.out.println("Cannot purchase food item. Not enough points in card.");
        }
    }

    @Override
    public String toString() {
        return String.format("Balance: %,d\n",getPoints());
    }


}