Assignment 3 Tic-Tac-Toe game

Assignment 3

Objective
This assignment should give you practice with classes, command-line arguments,
and inheritance.
Task
Write a Tic-Tac-Toe game which will be played and drawn with text characters
on the console. Your main program should be in a class called TicTacToe and
you must have at least the following two files:
• TicTacToe.java
• Player.java
You may build other classes in other files. How exactly you design this
program and what other files you create will be up to you. Everything will
be packed up into a runnable jar file at the end. Each file should have a
comment including your name at the top of the file. Each file should
also have appropriate comments throughout.
Requirements
1. Storage and setup: You can design this with as many or as few classes as
you like, as long as you are using at least the two classes described above.
The game must begin with the main() method in class TicTacToe. You
must use a 3×3 two-dimensional array to store the game board information
(store it as member data of a class, you can choose the type of storage).
Suggestion: Try to design your classes for re-usability. If you changed
things, such as porting your game logic to a GUI interface, how easy
would it be?
Another suggestion: Construct a main “game loop” that runs the game
logic until game over. This will be easier if you set up base class variables
for a generic player class, then attach objects for the player types used in
a given game using polymorphism.
2. Player options: You should allow the options of two human players, a
human player and a computer player, or two computer players. This will
be controlled through command line options when starting the program.
First player will have X, the second player will have O. The command
format for player options is:
java TicTacToe [-c [1|2]]
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The “-c” option indicates computer player(s). The optional “1|2” allows
the user to specify which player will be the computer player. Omitting
the “-c” option means two human players (the default). The possible
combinations are:
java TicTacToe // two human players
java TicTacToe -c // two computer players
java TicTacToe -c 1 // computer is player 1, human player 2
java TicTacToe -c 2 // human player 1, computer player 2
If the command is invalid usage (illegal options), print a usage message,
as below, then exit the program:
Usage: java TicTacToe [-c [1|2]]
3. Board output and player interface: The output of the board should
be in ASCII text format and needs to be user friendly. When asking a
human player for a move, let them type in just the number of a square
(a single number). Whenever an invalid cell is chosen by a human player
(already filled or out of range), print an error message and have them
re-enter. Player 1 will always be X and will go first (whether human
or computer). Player 2 will always be O. See below for some suggested
output.
4. Computer Player Rules: The computer player should not just use
random moves. It needs to follow the following rules, in this order of
priority:
(a) If a winning move is available, take it.
(b) If the opponent is threatening a win, block it (Note that if the opponent has two winning plays, only one can be blocked).
(c) If the center space is available, take it.
(d) Choose randomly between any remaining squares.
Note that with the above logic, it is possible to beat the computer player.
5. End of Game: If somebody wins, determine and print out which player
was the winner. If the game ends with no winner, print out that it was a
draw.
6. Randomness: Whenever the computer player has to make a random
choice, each choice must have an equal chance of being picked (so, if there
is a choice of 3 squares, you should pick a random number in a range of 3,
etc.). If you try to choose a random number between 1 and 9, then check
if the square is available, there is a small chance that your program could
run a long time and never pick a valid square.
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Some Suggested Libraries/Classes
• String
• StringBuilder
• java.util.Random
• java.util.Scanner
• java.lang.Integer
Also, notice that there is a good opportunity to use inheritance and polymorphism in the game play. It also may be useful to create an enum for the space
type.
Sample Output
(user input is underlined)
Game Board: Positions:
| | 1 | 2 | 3
----------- -----------
| | 4 | 5 | 6
----------- -----------
| | 7 | 8 | 9
Player 1, please enter a move(1-9): 9
Game Board: Positions:
| | 1 | 2 | 3
----------- -----------
| | 4 | 5 | 6
----------- -----------
| | X 7 | 8 | 9
Player 2 chooses position 5
Game Board: Positions:
| | 1 | 2 | 3
----------- -----------
| O | 4 | 5 | 6
----------- -----------
| | X 7 | 8 | 9
Player 1, please enter a move(1-9): 1
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Game Board: Positions:
X | | 1 | 2 | 3
----------- -----------
| O | 4 | 5 | 6
----------- -----------
| | X 7 | 8 | 9
Player 2 chooses position 4
Game Board: Positions:
X | | 1 | 2 | 3
----------- -----------
O | O | 4 | 5 | 6
----------- -----------
| | X 7 | 8 | 9
Player 1, please enter a move(1-9):
Extra Credit
Add a command line option “-a”, which stands for “advanced.” This option, if
used, makes the computer players take their turns with more advanced logic, as
follows:
1. If a winning move is available, take it
2. If the opponent is threatening a winning move, block it
3. Determine which squares can be played that will not eventually result in
a loss, and choose randomly between them
In other words, on the advanced setting, a computer player will always play
smart enough to not lose. On this setting, any game will result in a tie if a
human is using the optimal strategy; otherwise, the computer will win. Exactly
how you create the logic for the 3rd part of the computer’s logic is up to you,
as long as the computer can never lose (which is possible, as Tic-Tac-Toe is a
solved game).
Sample command line usage:
java TicTacToe -c 1 -a // player 1 is computer on advanced setting
Note that the -a option only makes sense if the -c option is used. If you do the
extra credit, the usage message would now be:
Usage: java TicTacToe [-c [1|2] [-a]]
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Submitting
Pack all of your files (class files and source code) into a fully runnable JAR
file called hw3.jar. The main program that the jar file should execute should
be in class TicTacToe. I should be able to run the main() method from your
file with the command:
java -jar hw3.jar
Submit your jar file via the Blackboard submission link for assignment 3.
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