不寻常的"静态"方法声明

Question

public class Card {

    public enum Rank { DEUCE, THREE, FOUR, FIVE, SIX,
        SEVEN, EIGHT, NINE, TEN, JACK, QUEEN, KING, ACE }

    public enum Suit { CLUBS, DIAMONDS, HEARTS, SPADES }

    private final Rank rank;
    private final Suit suit;
    private Card(Rank rank, Suit suit) {
        this.rank = rank;
        this.suit = suit;
    }

    public Rank rank() { return rank; }
    public Suit suit() { return suit; }
    public String toString() { return rank + " of " + suit; }

    private static final List<Card> protoDeck = new ArrayList<Card>();

    // Initialize prototype deck
    **static** {
        for (Suit suit : Suit.values())
            for (Rank rank : Rank.values())
                protoDeck.add(new Card(rank, suit));
    }

    public static ArrayList<Card> newDeck() {
        return new ArrayList<Card>(protoDeck); // Return copy of prototype deck
    }
}

我有一个快速的问题.在静态关键字声明之后立即启动的代码块,是什么类型的方法？我以前从未见过这个.如果有人能够启发我,那将非常感激.谢谢.

Answer 1

这不是方法,而是类的静态初始化块.您可以在Java语言规范中阅读有关它的更多信息.

加载类后,内部代码执行一次.