Poker Simulator Design Writeup
Contents |
Elliot Fisher's Design
Intro
For my design study I have chosen to create a poker simulator of sorts. I have started this project specifically for the 427 design study. Cards are dealt to a number of players around a table, the hand played through and the winner of the hand determined. The game can continue for an arbitrary number of hands. Currently the user controls each player in turn and can see all the Player's cards, so it is more of a simulator than a full blown poker game. Ideally if I had more time it would be nice to make it multiplayer with some client server functionality, or to implement some AI to play against. I have implemented the Texas Hold 'em variant of poker (see A Brief Introduction to Poker below), but have left the design open for the implementation of other poker variants and rules. To illustrate this there are classes for the Draw variant of poker and the Wildcard rule in the design, but without full functionality. I have also implemented the "cash game" type of poker, where the game consists of one table and players can come or go as they wish. Alternately a poker game can be "tournament" style, which consists of one or more tables and players aim to win the tournament by taking other players chips and knocking them out until there is one player left. As players are knocked out the tables are balanced and joined together until there is one table; the "final table." I have created a Tournament class to illustrate this possibility, but there is currently no functionality for it.
Haven't had time to implement: There are also different bet limits in poker, I am not sure how this might effect my design if they are to be implemented in the future. The most common is No Limit where you can bet however much you like at any time, even your entire chip stack. There are also Limit games where bets and raises are limited to a fixed amount, and Pot Limit where bets are limited to the size of the pot.
A Brief Introduction to Poker
Poker is a card game where players make bets on the value of the cards in their hand, which accumulate in a central pot. The winner is the player with the highest ranked hand, or the last player to remain in the hand after all other players have folded. In order to stay in contention for the pot a player must match the bet of every other player in the pot. If a player doesn't wish to match a bet, they may fold their hand at any time, making them out of contention for the pot. Play is commenced clockwise around the table from the left of the player in the dealer position. After the hand is completed, the player to the left of the dealer assumes the dealer position for the next hand.
The poker variant implemented in my design is called Texas Hold 'em, and is the most popular form of poker today. In a game of Texas Hold 'em, each player is dealt only two cards face down (the hole cards). A total of five community cards are dealt face up on the table, and each player must make the best possible five card hand using any combination of community cards and their own cards. The first betting round is performed after the players receive their two hole cards. Once this is complete, three community cards are dealt (the flop), and another betting round performed. After this a fourth community card is dealt (the turn), followed by a betting round, then the last community card is dealt (the river), followed by the last betting round.
Betting rounds consist of players either checking (opting to bet nothing if there is no current bet to match), calling an existing bet by putting out the equivalent amount of chips, or raising an existing bet by putting out a greater amount of chips than the existing bet. The winner of the hand wins the money in the pot, or in the case of a draw (two or more players having a hand of equivalent rank) the money is split between the players.
For more information I will refer the reader to Wikipedia. (I love Wikipedia, Wiki Wiki Pedia).
- Texas Hold 'em rules: [Texas Hold 'em]
- Poker hand rankings: [Hand ranks]
- Information about different poker variants: [Poker Variants]
Source Code
My source code is written in Java and can be found here: media:pokerSimulatorCode.tgz
To run it from a shell, type: java PokerSimulator [-gameType] [-variant]
-gameType is either Cash Game (-c) or Tournament (-t). Currently only (-c) is implemented.
-variant specifies the poker variant. Currently only (-h) for HoldEm is implemented.
Class Diagram
Design Breakdown
Design Patterns
Observer: Dealer Observable: TablePot
Template Method: CardAnalyser.analyseCards()
State: RankedHand.compareTo
Abstract Factory: PokerStyleFactory
Singleton: PokerGame
Iterator: used throughout RegularCardAnalyser to iterate though Sets of Cards.
