package bingo.game;import java.rmi.*;import java.rmi.server.*;import java.util.Random;import bingo.shared.*;class RegistrarImpl extends UnicastRemoteObject implements Registrar, Constants{    private RingMaster ringMaster;    private GameParameters gameParameters;    private Roster roster;    RegistrarImpl(RingMaster ringMaster) throws RemoteException {	super();	this.ringMaster = ringMaster;	gameParameters = ringMaster.getGameParameters();	roster = ringMaster.getRoster();    }    public String whatsHappening() throws RemoteException {	return ringMaster.statusString();    }    public Ticket mayIPlay(String playerName, int numCards, long seed)                                   throws RemoteException    {	if (!ringMaster.ready())	    return new Ticket("BINGO server not ready. You can't play.");	else if (!ringMaster.isRegistering())	    return new Ticket("Registration not open. You can't play.");	    	if (numCards > gameParameters.getMaxCards())	    numCards = gameParameters.getMaxCards();	synchronized (roster) {	    if (roster.size() == gameParameters.getMaxPlayers())	        return new Ticket("Game full. You can't play.");	    Card[] cards = new Card[numCards];            Random generator = new Random(seed);	    for (int i = 0; i < numCards; i ++)	        cards[i] = new Card(generator);	    ringMaster.signTheCards(cards);	    PlayerRecord p = new PlayerRecord(roster.nextPlayerID(), playerName, numCards);	    String welcomeMessage = "Welcome to game # " + ringMaster.getGameNumber() + ".";	    Ticket ticket = new Ticket(welcomeMessage, p.ID, cards);	    roster.addElement(p, ringMaster);	    return ticket;	}    }    public Answer BINGO(int playerID, Card c) throws RemoteException {	PlayerRecord p = roster.searchForPlayerWithID(playerID);	if (p == null)	    return new Answer(false, "Can't find player with ID: " + playerID + ".");	if (p.wolfCries >= MAX_WOLF_CRIES)	    return new Answer(false, "Sorry, wolf cryer, you're out of the game.");	synchronized (ringMaster) {	    ringMaster.setCheckingForWinner();	    if (ringMaster.verify(c)) {	        ringMaster.setGameOver();	        return new Answer(true, "You won! Congratulations!");	    } else {		p.wolfCries++;	        ringMaster.setGameResumed();	        ringMaster.sendPlayerStatusMessage(p);		if (p.wolfCries == MAX_WOLF_CRIES) {	            return new Answer(false, "You've cried wolf 3 times. You're out.");		} else {	            return new Answer(false, "You cried wolf..." +				      (MAX_WOLF_CRIES - p.wolfCries) +				      " more and you're out.");		}	    }	}    }}