我现在已经坚持了一段时间，目标是创建一个阵列来保持卡片，一旦我创建阵列打印出来，唯一的卡片就是打印的心脏之王。为什么不迭代？
public class Card
{
// Card suits (provided for your convenience - use is optional)
public static final int SPADES = 0;
public static final int HEARTS = 1;
public static final int CLUBS = 2;
public static final int DIAMONDS = 3;
// Card faces (provided for your convenience - use is optional)
public static final int ACE = 1;
public static final int TWO = 2;
public static final int THREE = 3;
public static final int FOUR = 4;
public static final int FIVE = 5;
public static final int SIX = 6;
public static final int SEVEN = 7;
public static final int EIGHT = 8;
public static final int NINE = 9;
public static final int TEN = 10;
public static final int JACK = 11;
public static final int QUEEN = 12;
public static final int KING = 13;
// define fields here
private static int suit;
private static int val;
private String[] suits = {"Clubs", "Spades", "Diamonds", "Hearts"};
private String[] vals = {"Ace","2", "3", "4", "5", "6", "7",
"8", "9", "10", "Jack", "Queen", "King" };
// This constructor builds a card with the given suit and face, turned face down.
public Card(int suit, int val)
{
this.val = val;
this.suit = suit;
}
public @Override String toString()
{
return vals[val] + " Of " + suits[suit];
}
// This method retrieves the suit (spades, hearts, etc.) of this card.
public int getSuit()
{
return this.suit;
}
// This method retrieves the face (ace through king) of this card.
public int getFace()
{
// return this.val;
switch(val)
{
case 0 : return 1;
case 1 : return 2;
case 2 : return 3;
case 3 : return 4;
case 5 : return 6;
case 6 : return 7;
case 7 : return 8;
case 8 : return 9;
case 9 : return 10;
case 10 : return 10;
case 12 : return 10;
default : return 0;
}
}
}`
import java.util.ArrayList;
import java.util.Random;
// This class represents the deck of cards from which cards are dealt to players.
public class Deck
{
//array
public static Card[] cards;
// private static ArrayList<Card> cards;
int i;
int counter;
// This constructor builds a deck of 52 cards.
Deck()
{
i = 51;
//array implementation
cards = new Card[52];
int x = 0;
for(int i = 0; i < 4; i++)
{
for(int j = 0; j < 13;j++)
{
//Array implementation
cards[x] = new Card(i,j);
x++;
}
}
}
// This method takes the top card off the deck and returns it.
public Card deal()
{
//Array implementation
int index = 0;
Card temp = cards[index];
return temp;
}
// this method returns true if there are no more cards to deal, false otherwise
public boolean isEmpty()
{
if(cards.length == 0)
{
return true;
}
return false;
}
//this method puts the deck int some random order
// public void shuffle()
// {
// for(int i = 51; i > 0; i--)
// {
// int rand = (int) (Math.random() * (i+1));
// Card temp = this.cards[i];
// this.cards[i] = cards[rand];
// cards[rand] = temp;
// }
//
// }
}
public class BlackJack extends Deck
{
public static void main(String []args)
{
System.out.println("Ready to play a game of BlackJack?");
Deck deck = new Deck();
for(int i = 0; i < cards.length;i++)
{
System.out.println(cards[i]);
}
答案 0 :(得分：5)
问题是由以下原因引起的：
// define fields here
private static int suit;
private static int val;
因为它们是静态的，所有Card实例都共享这些，所以它们都将具有它们设置的最后一个值。删除静态。
答案 1 :(得分：1)
为您提供一些提示，以便您可以更轻松地阅读/维护代码：
此代码的错误/不正常的一面是：
public class CardGame {
static public enum SuitType {
SPADES, HEARTS, CLUBS, DIAMONDS
}
static public enum FaceType {
ACE("Ace", 1), //
TWO("2", 2), //
THREE("3", 3), //
FOUR("4", 4), //
FIVE("5", 5), //
SIX("6", 6), //
SEVEN("7", 7), //
EIGHT("8", 8), //
NINE("9", 9), //
TEN("10", 10), //
JACK("Jack", 11), //
QUEEN("Queen", 12), //
KING("King", 13), //
;
private final String mName;
private final int mValue;
private FaceType(final String pName, final int pValue) {
mName = pName;
mValue = pValue;
}
public String getName() {
return mName;
}
public int getValue() {
return mValue;
}
public int getValue_alternative() {
return ordinal() + 1; // ordinal is the index of the enum, starting at ace=0 ... king=12
// sorting and comparing of suits could also be done by .ordinal() if need be
}
}
static public class Card {
private final SuitType mSuit;
private final FaceType mFace;
public Card(final SuitType pSuit, final FaceType pFace) {
mSuit = pSuit;
mFace = pFace;
}
public SuitType getSuit() {
return mSuit;
}
public FaceType getFace() {
return mFace;
}
@Override public String toString() {
return mFace.getName() + " of " + mSuit + " - " + mFace.getValue() + (mFace.getValue() > 1 ? " points" : " point");
}
}
static public class Deck {
private final ArrayList<Card> mCards;
public Deck() {
mCards = createFullDeck();
}
private ArrayList<Card> createFullDeck() { // can also be static as it dowes not use member cariables => potential factory method
final ArrayList<Card> ret = new ArrayList<>();
for (final SuitType suit : SuitType.values()) {
for (final FaceType face : FaceType.values()) {
final Card c = new Card(suit, face);
ret.add(c);
}
}
return ret;
}
public void shuffleRandomly() {
final ArrayList<Card> tempList = new ArrayList<>();
tempList.addAll(mCards);
mCards.clear();
while (tempList.size() > 0) {
final int index = (int) (Math.random() * tempList.size());
final Card card = tempList.remove(index);
mCards.add(card);
}
}
public void print() {
System.out.println(" - - - DECK BEGINS - - - ");
int counter = 0;
for (final Card c : mCards) {
System.out.println("\t" + c);
++counter;
}
System.out.println("> Printed " + counter + " cards.");
System.out.println(" - - - DECK ENDS - - - ");
}
}
public static void main(final String[] args) {
final Deck d = new Deck();
d.print();
d.shuffleRandomly();
d.print();
}
}