J2ME: Tic Tac Toe

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J2ME Tic Tac Toe

• By Jud Porter and John Tat

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Goals for Project

• Design and implement multiplayer game
• Network connectivity between mobile devices
• Keep scoring for the game
• Implement a cursor to select positions

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Why Tic Tac Toe?

• Simple game to implement
• Framework can be used to implement more complex
  game
• Designed and implemented in J2ME
• Java Micro Edition
• Wireless Toolkit 2.2
• Generic toolkit instead of vendor specific
• Better chance of working on a variety of devices

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J2ME and Wireless Toolkit

• Device that program is implemented on must be
  specified
• Device implements profile
• Profiles are built upon configuration
• MIDP 2.0
• Mobile Information Device Profile 2.0
• CLDC 1.1
• Connection Limited Device Configuration 1.1

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Tic Tac Toe Classes

• TacTacToeMidlet
• First class that runs
• Allows the user to select between Client and
  Server
• Creates a new instance of Client or Server
  depending on choice
• TicTacToeCanvas
• Drawing of the board
• Key Pressed
• Check for winner
• Keeps track of scores
• Updates opponents pieces

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Tic Tac Toe Classes Contd

• TicTacToeServer
• Creates instance of TicTacToeCanvas class
• Communication scheme with client
• First to move
• Sends an integer to client of grid selection
• Waits to receive integer for client of grid
  selection
• TicTacToeClient
• Creates instance of TicTacToeCanvas class
• Communication scheme with server
• Wait for server to move
• receives the integer and places a piece
  accordingly onto the board

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Game Structure
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Communication Scheme

• Bluetooth
• Protocol too difficult for scope of this project
• Could not get simple application to work
• Other Protocols Datagram, Socket, COMM
• Moved onto Socket Protocol
• Endpoint for communication of two devices
• Socket connection on port localhost 5000
• InputStream and OutputStream are opened when
  server discovers the client or client finds
  server
• Two way communication scheme

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Communication Scheme

• Server has first move
• Client waits for server to move
• On move (when Fire key is pressed) location of
  move encoded as integer is sent to other device
• On receipt of location, other client now has
  control of board to send next move

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TicTacToeCanvas

• Paint
• Draws board
• Draws pieces
• Draws cursor
• SetPiece
• Stores client/server moves
• Change turns
• keyPressed
• Moves the cursor on the screen
• Selects the board position and sends it to the
  client/server
• CheckWinner
• Checks for a winner
• Reset
• Resets the board for both client and server

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Server/Client Screenshots
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Game Screenshots
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Winner Screenshots