java - 观察者设计模式，我是不是搞反了？

Question

我所在的类(class)正在实现大富翁游戏模拟，非常简单，只需将每次回合的结果打印到控制台供用户查看，最终我们会将其移动到 GUI，但现在我们只是S.o.P 到控制台每个玩家的回合结果。

这些结果是从 Player 类打印的。玩家类基本上将打印所需的所有信息保存在一个位置(即，playerName、rollTotal、origSquareLocation、newSquareLocation)。

我正在尝试围绕观察者设计模式进行思考，并使 MonopolyGame 类成为观察者，让 Player 类成为可观察者。这是可能的还是因为 MonopolyGame 类正在构建玩家而将其倒退？我需要创建一个单独的 GameObserver 类才能完成这项工作吗？

这是我的 MonopolyGame 类:

public class MonopolyGame {

    private static final int ROUNDS_TOTAL = 40;
    private static final int PLAYERS_TOTAL = 2;
    private List<Player> players = new ArrayList<Player>(PLAYERS_TOTAL);
    private Board board = new Board();
    private Die[] dice = { new Die(), new Die() };

    /**
     * Default Constructor
     */
    public MonopolyGame() {

        Player p = new Player("Horse", dice, board);
        players.add(p);
        p = new Player("Car", dice, board);
        players.add(p);
    }

    /**
     * Method: playGame()
     * 
     * starts a new MonopolyGame for the assigned amount of rounds.
     */
    public void playGame() {

        for (int i = 0; i < ROUNDS_TOTAL; i++) {
            playRound();
        }
    }

    /**
     * Method: playRound()
     * 
     * allows each player by iterator to take their turn for each round played.
     */
    public void playRound() {
        for (Iterator<Player> iter = players.iterator(); iter.hasNext(); ) {
            Player player = iter.next();
            player.takeTurn();
        }
    }

} // End MonopolyGame Class

这是我的玩家类别:

public class Player {

    private String name;
    private Piece piece;
    private Board board;
    private Die[] dice;

    public Player(String name, Die[] dice, Board board) {
        this.name = name;
        this.dice = dice;
        this.board = board;
        this.piece = new Piece(board.getStartSquare());
    }

    public void takeTurn() {

        // Roll the dice
        int rollTotal = 0;
        for (int i = 0; i < dice.length; i++) {
            dice[i].roll();
            rollTotal += dice[i].getFaceValue();
        }

        // place the Players piece in the correct location.
        Square newLoc = board.getSquare(piece.getLocation(), rollTotal);
        piece.setLocation(newLoc);

        System.out.println(getName() + " has rolled a " + rollTotal + " and landed on " + getLocation().getName()); 
    }

    public Square getLocation() {
        return piece.getLocation();
    }

    public String getName() {
        return name;
    }

} // End Player Class

Answer 1

当然这是该模式的可能用途。但更自然地(至少对我来说)该模式的用法是像“ConsolePrinter”或“GuiBoardWindow”作为观察者，而游戏(或玩家)作为可观察者。由于观察者模式的主要思想是解耦不直接相关的部分。游戏的状态和玩家对象对我来说非常重要，以至于您可能不想将它们解耦。至少只要相邻的玩家或游戏不是游戏机制的实际模型/实体之外的任何东西。