java - 从卡牌数组中调用一张卡牌

Question

我正在进行一项关于创建一副纸牌的 Java 实验，但在其中一个部分遇到了问题。对于这一部分，我必须有一个接受整数参数并返回 Card 对象的方法。它应该返回对牌组数组中(0 到 NUMBERS-1)中的卡片对象的引用。如果索引不在范围内，则必须返回 null。我尝试使用牌组[输入参数]来做到这一点，但意识到这不起作用，因为牌组是纸牌。我不确定该怎么做。我应该改变什么才能让它正常工作？谢谢!

public class DeckOfCards {
    public static final int NUMBERS = 52;
    public Card[] deck = new Card[NUMBERS];

    String[] ranks = {"Ace", "2", "3", "4", "5", "6", "7", "8", "9", "10", "Jack", "Queen", "King"};
    String[] suits = {"Clubs", "Diamonds", "Hearts", "Spades"};

    public DeckOfCards() {
        int i = 0;
        for(String rank : ranks) {
            for(String suit : suits) {
                deck[i] = new Card(rank, suit);
                i++;
            }
        } 

    }

    public Random random = new Random();

    public void shuffle() {
        for(int i = 0; i < 500; i++) {
            int firstRandomCard = random.nextInt(NUMBERS - 1);
            int secondRandomCard = random.nextInt(NUMBERS - 1);

            Card firstCard = deck[firstRandomCard];
            Card secondCard = deck[secondRandomCard];

            deck[firstRandomCard] = secondCard;
            deck[secondRandomCard] = firstCard;

        }
    }

    //this is where I am having problems.
    public int getCardAt(int number) {
        if (number < 0 || number > NUMBERS - 1)
            return null;
        else 
            return deck[number];
    }  
}    

Answer 1

我认为您的 getCardAt 方法签名是错误的。

您希望它返回一个 Card 而不是 int。