01: import java.util.HashSet;
02: import java.util.Iterator;
03: import java.util.Set;
04: 
05: /**
06:    A program to test hash codes of coins
07: */
08: public class HashCodeTest
09: {
10:    public static void main(String[] args)
11:    {
12:       Coin coin1 = new Coin(0.25, "quarter");
13:       Coin coin2 = new Coin(0.25, "quarter");
14:       Coin coin3 = new Coin(0.05, "nickel");
15: 
16:       System.out.println("hash code of coin1=" 
17:          + coin1.hashCode());
18:       System.out.println("hash code of coin2=" 
19:          + coin2.hashCode());
20:       System.out.println("hash code of coin3=" 
21:          + coin3.hashCode());
22: 
23:       Set coins = new HashSet();
24:       coins.add(coin1);
25:       coins.add(coin2);
26:       coins.add(coin3);
27: 
28:       Iterator iter = coins.iterator();
29:       while (iter.hasNext())
30:          System.out.println(iter.next());
31:    }
32: }