Question

I am making a game like Rock Paper Scissors called fire water stick where the rules are

1. Stick beats Water by floating on top of it

2. Water beats Fire by putting it out

3. Fire beats Stick by burning it

The TODOS are as follows:

TODO 1: Declare the instance variables of the class. Instance variables are private variables that keep the state of the game. The recommended instance variables are:

1.

2. 3. 4. 5. 6.

A variable, “rand” that is the instance of the Random class. It will be initialized in a constructor (either seeded or unseeded) and will be used by the getRandomChoice() method.
A variable to keep the player’s cumulative score. This is the count of the number of times the player (the user) has won a round. Initial value: 0.

A variable to keep the computer’s cumulative score. This is the count of the number of times the computer has won a round. Initial value: 0.

A variable to keep the count of the number of rounds that have been played. Initial value: 0.

A variable to keep track of if the player has won the current round (round-specific): true or false. This would be determined by the playRound method. Initial value: false.

A variable to keep track of if the player and computer have tied in the current round (round-specific): true or false. This would be determined by the playRound method. Initial value: false.

The list above contains the minimum variables to make a working program. You may declare more instance variables as you wish.

TODOs 2 and 3: Implement the constructors. The constructors assign the instance variables to their initial values. In the case of the Random class instance variable, it is initialized to a new instance of the Random class in the constructors. If a constructor has a seed parameter, the seed is passed to the Random constructor. If the constructor does not have a seed parameter, the default (no parameter) Random constructor is called.

TODO 4: This method returns true if the inputStr passed in is one of the following: "S", "s", "W", "w", "F", "f", false otherwise. Note that the input can be upper or lower case.

TODOs 5, 6, 7, 8, 9, 10 These methods just return the values of their respective instance variables.

TODO 11: This is a private method that is called by the playRound method. It uses the instance variable of the Random class to generate an integer that can be “mapped” to one of the three Strings: "S", "W", "F", and then returns that String, which represents the computer’s choice.

TODO 12: The playRound method carries out a single round of play of the SWF game. This is the major, “high-level” method in the class. This method does many tasks including the following steps:

Here is my code that is not giving the correct output:

1 import java.util.Random;
2
3 public class StickWaterFireGame {
4
5 private int playerScore;
6 private int computerScore;
7 private int rounds;
8 private boolean playerWins;
9 private boolean isTie;
10 private Random rand;
11 private String playerChoice;
12 private String computerChoice;
13
14
15 public StickWaterFireGame() {
16
17 rand = new Random();
18 playerScore = 0;
19 computerScore = 0;
20 rounds = 0;
21 playerWins = false;
22 isTie = false;
23 playerChoice = "";
24 computerChoice = "";
25
26 }
27
28
29 public StickWaterFireGame(int seed) {
30
31 rand = new Random(seed);
32 playerScore = 0;
33 computerScore = 0;
34 rounds = 0;
35 playerWins = false;
36 isTie = false;
37 playerChoice = "";
38 computerChoice = "";
39
40 }
41
42 public boolean isValidInput(String inputStr) {
43
44 if (inputStr.equalsIgnoreCase("s")) {
45
46 return true;
47
48 }
49
50 else if (inputStr.equalsIgnoreCase("w")) {
51
52 return true;
53
54 }
55
56 else if (inputStr.equalsIgnoreCase("f")) {
57
58 return true;
59
60 }
61
62 else {
63
64 return false;
65
66 }
67
68 }
69
70
71
72 public String getComputerChoice(){
73
74 computerChoice = getRandomChoice();
75 return computerChoice;
76 }
77
78 public boolean playerWins(){
79
80 if ((playerChoice.equals("S")) && (computerChoice.equals("W"))) {
81
82 return true;
83
84 }
85
86 else if ((playerChoice.equals("W")) && (computerChoice.equals("F"))) {
87
88 return true;
89
90 }
91
92 else if ((playerChoice.equals("F")) && (computerChoice.equals("S"))) {
93
94 return true;
95
96 }
97
98 else {
99
100 return false;
101
102 }
103
104 }
105
106
107 public int getPlayerScore(){
108
109 return playerScore;
110
111 }
112
113
114 public int getComputerScore(){
115
116 return computerScore;
117
118 }
119
120
121 public int getNumRounds(){
122
123 return rounds;
124
125 }
126
127
128 public boolean isTie(){
129
130 if (playerChoice.equals(computerChoice)){
131
132 return true;
133
134 }
135
136 else{
137
138 return false;
139
140 }
141
142 }
143
144
145 private String getRandomChoice() {
146
147 int num;
148 Random rand = new Random();
149 num = rand.nextInt(3);
150 String computerChoice = "";
151
152 if (num == 0){
153
154 computerChoice = "S";
155
156 }
157
158 else if (num == 1){
159
160 computerChoice = "W";
161
162 }
163
164 else if (num == 2){
165
166 computerChoice = "F";
167
168 }
169
170 return computerChoice;
171
172 }
173
174
175
176 public void playRound(String playerChoice) {
177
178 if (isValidInput(playerChoice)){
179
180 this.playerChoice = playerChoice.toUpperCase();
181 rounds++;
182 this.computerChoice = getRandomChoice();
183
184 if(playerWins() == true) {
185
186 playerScore++;
187 playerWins = true;
188
189 }
190
191 else if (isTie() == true){
192
193 isTie = true;
194 playerWins = false;
195
196 }
197
198 else{
199
200 computerScore++;
201 playerWins = false;
202
203 }
204
205 }
206
207 else{
208
209 rounds++ ;
210 computerScore++ ;
211 }
212
213 playerWins = false;
214 isTie = false;
215
216 }
217 }

Answer 1

modified code is as below(marked as bold are the changes) :

import java.util.Random;

public class StickWaterFireGame {
   private int playerScore;
   private int computerScore;
   private int rounds;
   private boolean playerWins;
   private boolean isTie;
   private Random rand;
   private String playerChoice;
   private String computerChoice;

   public StickWaterFireGame() {
       rand = new Random();
       playerScore = 0;
       computerScore = 0;
       rounds = 0;
       playerWins = false;
       isTie = false;
       playerChoice = "";
       computerChoice = "";
   }

   public StickWaterFireGame(int seed) {
       rand = new Random(seed);
       playerScore = 0;
       computerScore = 0;
       rounds = 0;
       playerWins = false;
       isTie = false;
       playerChoice = "";
       computerChoice = "";
   }

   public boolean isValidInput(String inputStr) {
       if (inputStr.equalsIgnoreCase("s")) {
           return true;
       } else if (inputStr.equalsIgnoreCase("w")) {
           return true;
       } else if (inputStr.equalsIgnoreCase("f")) {
           return true;
       } else {
           return false;
       }
   }

   public String getComputerChoice() {
       //computerChoice = getRandomChoice();//remove this line of code
       return computerChoice;
   }

   public boolean playerWins() {
       if ((playerChoice.equals("S")) && (computerChoice.equals("W"))) {
           return true;
       } else if ((playerChoice.equals("W")) && (computerChoice.equals("F"))) {
           return true;
       } else if ((playerChoice.equals("F")) && (computerChoice.equals("S"))) {
           return true;
       } else {
           return false;
       }
   }

   public int getPlayerScore() {
       return playerScore;
   }

   public int getComputerScore() {
       return computerScore;
   }

   public int getNumRounds() {
       return rounds;
   }

   public boolean isTie() {
       if (playerChoice.equals(computerChoice)) {
           return true;
       } else {
           return false;
       }
   }

   private String getRandomChoice() {
       int num;
       // Random rand = new Random();
       num = rand.nextInt(3);// here we can directly use rand(instance variable)
       String computerChoice = "";
       if (num == 0) {
           computerChoice = "S";
       } else if (num == 1) {
           computerChoice = "W";
       } else if (num == 2) {
           computerChoice = "F";
       }
       return computerChoice;
   }

   public void playRound(String playerChoice) {
       if (isValidInput(playerChoice)) {
           this.playerChoice = playerChoice.toUpperCase();
           rounds++;
           this.computerChoice = getRandomChoice();
           if (playerWins() == true) {
               playerScore++;
               playerWins = true;
           } else if (isTie() == true) {
               isTie = true;
               playerWins = false;
           } else {
               computerScore++;
               playerWins = false;
           }
       } else {
           rounds++;
           computerScore++;
           playerWins = false;
           isTie = false;
       }
       /*
       * i don't see why you are making these variables as false when a round is over,
       * as they represent stauts of current round, instead you should make them as
       * false for an invalid user choice, that's why i have commented it and pasted
       * in else above
       */
       // playerWins = false;
       // isTie = false;
   }
}

Main provided by you (unchanged):

public class StickWaterFireMain {

   public static void main(String[] args) {
       // StickWaterFireGame game = new StickWaterFireGame();
       StickWaterFireGame game = new StickWaterFireGame(1234);
       Scanner scan = new Scanner(System.in);
       boolean keepGoing = true;
       String playerChoice = "";

       // Greet the user and state the rules:
       System.out.println("Welcome to Stick-Water-Fire!\n");
       System.out.println("Rules:");
       System.out.println("\tYou will play against the computer for the specified number of rounds.");
       System.out.println("\tYou will make a choice: 'S', 'W', or 'F' to represent 'Stick', 'Water', or 'Fire'.");
       System.out.println("\tThe computer will also make a choice, and the winner is chosen as follows:");
       System.out.println("\t\t Stick beats Water (it floats on top)");
       System.out.println("\t\t Water beats Fire (extinguishes the fire)");
       System.out.println("\t\t Fire beats Stick (burns the stick)");
       System.out.println("\tIn the event of a tie, there is no winner.");
       System.out.println("\tEach round, the winner will have their score incremented.");
       System.out.println("\tA report of scores and number of rounds will be displayed at the end of each round.");
       System.out.println("\tEnter X to quit.");
       System.out.println("\tGood luck!");

       // begin the game loop.
       while (keepGoing) {
           System.out.println("Enter 'S' for Stick, 'W' for Water, 'F' for Fire, or X to quit:");
           playerChoice = scan.nextLine();
           if (playerChoice.equalsIgnoreCase("X")) {
               keepGoing = false;
           }
           else { // Handle round of play
               // validate input
               if (!game.isValidInput(playerChoice)) {
                   System.out.println("\tInvalid input entered: " + playerChoice + "\n");
               }
               else {
                   game.playRound(playerChoice);
                   String computerChoice = game.getComputerChoice();
                   System.out.println("You chose " + playerChoice + " and the computer chose " + computerChoice);
                   // report winner
                   if (game.isTie()) {
                       System.out.println("You tied!");
                   } else if (game.playerWins()) {
                       System.out.println("You won! Nice job!\n");
                   } else { // Computer won
                       System.out.println("You lost. Better luck next time!\n");
                   }
                   // Print report
                   System.out.println("Game summary:");
                   System.out.println(getScoreReportStr(game));
                   System.out.println(" ");
               }
           } // end of round
       } // end loop
       System.out.println("Thanks for playing!");
   } // end main

   public static String getScoreReportStr(StickWaterFireGame game) {
       return "Total plays: " + game.getNumRounds() + "\nYour total score: " + game.getPlayerScore()
               + ", computer total score: " + game.getComputerScore();
   }

}

output when you run above class will be as below:

its working as required, please test it rigorously by yourself and let me know.

In case of a tie scores are not increased( highlighted in the output screenshot)

please comment if you need any help or suggestions to improve..

to format the code : Ctrl+a then Ctrl+Shift+f