package junit.samples.money;

/**
 * The common interface for simple Monies and MoneyBags
 * 
 */
public interface IMoney {
	/**
	 * Adds a money to this money.
	 */
	public abstract IMoney add(IMoney m);

	/**
	 * Adds a simple Money to this money. This is a helper method for
	 * implementing double dispatch
	 */
	public abstract IMoney addMoney(Money m);

	/**
	 * Adds a MoneyBag to this money. This is a helper method for implementing
	 * double dispatch
	 */
	public abstract IMoney addMoneyBag(MoneyBag s);

	/**
	 * Tests whether this money is zero
	 */
	public abstract boolean isZero();

	/**
	 * Multiplies a money by the given factor.
	 */
	public abstract IMoney multiply(int factor);

	/**
	 * Negates this money.
	 */
	public abstract IMoney negate();

	/**
	 * Subtracts a money from this money.
	 */
	public abstract IMoney subtract(IMoney m);

	/**
	 * Append this to a MoneyBag m. appendTo() needs to be public because it is
	 * used polymorphically, but it should not be used by clients because it
	 * modifies the argument m.
	 */
	public abstract void appendTo(MoneyBag m);
}