Five Dice Game Rick Mercer

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Five Dice GameRick Mercer

• An Example with
• Strategy, Observer, Composite, MVC Human Player
  v. computer player Selectable views
• Drawing
• Animation
• For the Risk and Pacman teams

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Specification

• Complete a game of five card dice that allows one
  human player to play a Yahtzee-like game of dice
  against two other computer players. The game
  rolls five dice for each player to see has the
  best initial roll. The best five dice wins using
  this ranking system
• FIVEOFAKIND, FOUROFAKIND, STRAIGHT (1,
  2, 3, 4, 5), FULLHOUSE (3 of a kind plus a
  pair), THREEOFKIND, TWOPAIR, PAIR
• Each player is then given a chance to reroll
• The highest hand after the second roll is
  declared the winner (sort of like 5 card draw
  poker)

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Particulars

• There must be two views of the dice game
• The computer players must have a different
  strategies for re-rolling an the human player has
  her own
• Have a menu to swap view and start new games
• Allow the human player to choose without a modal
  dialog
• Make the current player obvious

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Review Strategy Design Pattern

• Name Strategy (a.k.a Policy)
• Problem You want to encapsulate a family of
  algorithms and make them interchangeable.
  Strategy lets the the algorithm vary
  independently from the clients that use it (GoF)
• Solution Create an abstract class (or interface)
  and extend (or implement) it in numerous ways.
  Each subclass (or interface) defines the same
  method names in different ways

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Strategy Pattern (non-computer)

• Strategy http//www.agcs.com/supportv2/techpapers/
  patterns/papers/patexamples.htm
• A Strategy defines a set of algorithms that can
  be used interchangeably. Modes of transportation
  to an airport is an example of a Strategy.
  Several options exist, such as driving one's own
  car, taking a taxi, an airport shuttle, a city
  bus, or a limousine service. For some airports,
  subways and helicopters are also available as a
  mode of transportation to the airport. Any of
  these modes of transportation will get a traveler
  to the airport, and they can be used
  interchangeably. The traveler must chose the
  Strategy based on tradeoffs between cost,
  convenience, and time.

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Can plug in a strategy
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Strategy Pattern

• In Five Dice Game, design a strategy so different
  computer players can have different strategies
• Using the pattern from inside the model
• if(((ComputerPlayer)currentPlayer).doYouWantToRero
  ll(currentPlayer, getPlayers()))
• currentPlayer.rollAllDice()
• setChanged()
• notifyObservers(new Integer(currentPlayerInde
  x))

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Strategy with an interface

• // File ReRollStrategy.java
• import java.util.List
• public interface ReRollStrategy
• public boolean doYouWantToReroll(Player
  thisPlayer,
• List
  players)

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• // File BeginnerStrategy.java
• import java.util.
• public class BeginnerStrategy implements
  ReRollStrategy
• private static Random generator
• public BeginnerStrategy()
• generator new Random()
• // Beginners reroll 50 of the time, argument
  ignored
• public boolean doYouWantToReroll(Player
  thisPLayer
• List players)
  
• if(generator.nextInt(2) 0)
• return true
• else
• return false

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• // File IntermediateStrategy.java
• public class IntermediateStrategy
• implements
  ReRollStrategy
• // ReRoll when a higher hand is found in any
  player
• // Argument is used here
• public boolean doYouWantToReroll(Player
  thisPlayer, List players)
• Player ref null
• for( int j 0 j lt players.size() j )
• ref (Player)players.get(j)
• if(HandRanker.firstArgBigger(ref.getDiceArra
  y(),
• thisPlayer.getDiceArray()) gt 0)
• return true
• return false

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Player

• Each "computer" player has a setStrategy method
• The human player's decision will be decided by
  the user's selection at the GUI
• Here is the code that is in GameModel

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Executes every timer beat

• if (currentPlayer instanceof HumanPlayer)
• // Handle human user differently
• myTimer.stop()
• passButton.setEnabled(true)
• rerollButton.setEnabled(true)
• // advanceToNextPlayer message should be sent
• // when user has clicked reroll or pass buttons
• else // must be a computer player

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• // Defer to the computer player strategy,
• // one of which examines other players
• if (((ComputerPlayer)
• currentPlayer).doYouWantToReroll(currentPlay
  er,
• 
  getPlayers()))
• currentPlayer.rollAllDice()
• setChanged()
• notifyObservers(new Integer(currentPlayerIndex
  ))
• currentPlayerIndex (currentPlayerIndex 1)
  
• getNumberOfPlayers()
• tick
• myTimer.start()
• // end of handle timer tick

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Model

• The model has Player, GameModel, ImageCollection,
  HandRanker, a Strategy pattern

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View

• There are two views, both extend JPanel and
  implement Observer

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Controller

• In this case, one class that extends JFrame and
  listens to its own menu selections