public class Craps
6 {
7 // create random number generator for use in method rollDice
8 private Random randomNumbers = new Random();
9
10 // enumeration with constants that represent the game status
11 private enum Status { CONTINUE, WON, LOST };
12
13 // constants that represent common rolls of the dice
14 private final static int SNAKE_EYES = 2;
15 private final static int TREY = 3;
16 private final static int SEVEN = 7;
17 private final static int YO_LEVEN = 11;
18 private final static int BOX_CARS = 12;
19
20 // plays one game of craps
21 public void play()
22 {
23 int myPoint = 0; // point if no win or loss on first roll
24 Status gameStatus; // can contain CONTINUE, WON or LOST
25
26 int sumOfDice = rollDice(); // first roll of the dice
27
28 // determine game status and point based on first roll
29 switch ( sumOfDice )
30 {
31 case SEVEN: // win with 7 on first roll
32 case YO_LEVEN: // win with 11 on first roll
33 gameStatus = Status.WON;
34 break;
35 case SNAKE_EYES: // lose with 2 on first roll
36 case TREY: // lose with 3 on first roll
37 case BOX_CARS: // lose with 12 on first roll
38 gameStatus = Status.LOST;
39 break;
40 default: // did not win or lose, so remember point
41 gameStatus = Status.CONTINUE; // game is not over
42 myPoint = sumOfDice; // remember the point
43 System.out.printf( "Point is %d\n", myPoint );
44 break; // optional at end of switch
45 } // end switch
46
47 // while game is not complete
48 while ( gameStatus == Status.CONTINUE ) // not WON or LOST
49 {
50 sumOfDice = rollDice(); // roll dice again
51
52 // determine game status
53 if ( sumOfDice == myPoint ) // win by making point
54 gameStatus = Status.WON;
55 else
56 if ( sumOfDice == SEVEN ) // lose by rolling 7 before point
57 gameStatus = Status.LOST;
58 } // end while
59
60 // won or lost message
61 if ( gameStatus == Status.WON )
62 System.out.println( "Player wins" );
63 else
64 System.out.println( "Player loses" );
65 } // end method play
66
67 // roll dice, calculate sum and results
68 public int rollDice()
69 {
70 // pick random die values
71 int die1 = 1 + randomNumbers.nextInt( 6 ); // first die roll
72 int die2 = 1 + randomNumbers.nextInt( 6 ); // second die roll
73
74 int sum = die1 + die2; // sum of die values
75
76 // results of this roll
77 System.out.printf( "Player rolled %d + %d = %d\n",
78 die1, die2, sum );
79
80 return sum; // return sum of dice
81 } // end method rollDice
82 } // end class Craps





Figure 6.10. Application to test class Craps.
(This item is ed on page 253 in the print version)
1 // Fig. 6.10: CrapsTest.java
2 // Application to test class Craps.
3
4 public class CrapsTest
5 {
6 public static void main( String args[] )
7 {
8 Craps game = new Craps();
9 game.play(); // play one game of craps
10 } // end main
11 } // end class CrapsTest

Player rolled 5 + 6 = 11
Player wins
Player rolled 1 + 2 = 3
Player loses
Player rolled 5 + 4 = 9
Point is 9
Player rolled 2 + 2 = 4
Player rolled 2 + 6 = 8
Player rolled 4 + 2 = 6
Player rolled 3 + 6 = 9
Player wins
Player rolled 2 + 6 = 8
Point is 8
Player rolled 5 + 1 = 6
Player rolled 2 + 1 = 3
Player rolled 1 + 6 = 7
Player loses