1 package junit.samples.money;
2
3 /**
4 * The common interface for simple Monies and MoneyBags
5 */
6 public interface IMoney {
7 /**
8 * Adds a money to this money.
9 */
10 public abstract IMoney add(IMoney m);
11
12 /**
13 * Adds a simple Money to this money. This is a helper method for
14 * implementing double dispatch
15 */
16 public abstract IMoney addMoney(Money m);
17
18 /**
19 * Adds a MoneyBag to this money. This is a helper method for
20 * implementing double dispatch
21 */
22 public abstract IMoney addMoneyBag(MoneyBag s);
23
24 /**
25 * Tests whether this money is zero
26 */
27 public abstract boolean isZero();
28
29 /**
30 * Multiplies a money by the given factor.
31 */
32 public abstract IMoney multiply(int factor);
33
34 /**
35 * Negates this money.
36 */
37 public abstract IMoney negate();
38
39 /**
40 * Subtracts a money from this money.
41 */
42 public abstract IMoney subtract(IMoney m);
43
44 /**
45 * Append this to a MoneyBag m.
46 * appendTo() needs to be public because it is used
47 * polymorphically, but it should not be used by clients
48 * because it modifies the argument m.
49 */
50 public abstract void appendTo(MoneyBag m);
51 }