我目前正在尝试将我的代码转换为ArrayList，而我似乎无法使其正常工作。我正在运行整个程序，它告诉我索引输出界限。我确定忘记为卡添加阵列的大小，但我不知道如何添加它。谢谢你的帮助！
编辑：我得到的错误在底部。此外，它告诉我转到removeTop方法。那里看起来很好。
import java.util.Random;
import java.util.List;
import java.util.ArrayList;
public class CardPile {
private ArrayList<Card> cards = new ArrayList<Card>();
private static Random r = new Random(1);
public void addToBottom(Card c) {
if (this.cards.size() == 52) {
System.out.println("The CardPile is full. You cannot add any more Card objects.");
}
this.cards.add(c);
}
public Card removeCard(Card c) {
if (this.cards.contains(c)) {
this.cards.remove(c);
}
return null;
}
public Card removeTop() {
return this.cards.remove(0);
}
public int searchValue(int value) {
int count = 0,
for (int i = 0;i < this.cards.size();i++) {
if (this.cards.get(i).getValue() == value) {
count++;
}
}
//System.out.println("Count = "+count);
return count;
}
public Card[] removeAll(int value)
//System.out.println("(removeAll) cards ="+ cards);
int count = searchValue(value);
Card[] removed = new Card[count];
int deletedCount = 0;
int i = 0;
while (deletedCount < count) {
if (this.cards.get(i).getValue() == value) {
removed[deletedCount] = this.cards.remove(i);
deletedCount++;
} else {
i++;
}
}
return removed;
}
public int getNumberCards() {
return this.cards.size();
}
public String toString() {
if (this.cards.isEmpty()) {
return "";
}
String builder = "";
for (int i = 0;i < this.cards.size() - 1;i++) {
builder = builder + this.cards.get(i) + ", ";
}
builder = builder + this.cards.get(this.cards.size() - 1);
return builder;
}
public void shuffle() {
if (this.cards.isEmpty()) {
return;
}
for (int count = 0; count < 100000;count++) {
int i = r.nextInt(this.cards.size());
int j = r.nextInt(this.cards.size());
Card temp = this.cards.get(i);
this.cards.set(i, this.cards.get(j));
this.cards.set(j, temp);
}
}
public static CardPile makeFullDeck() {
CardPile deck = new CardPile();
for (int suit = 0;suit < 4;suit++) {
for (int value = 1; value <= 13;value++) {
deck.addToBottom(new Card(suit, value));
}
}
deck.shuffle();
return deck;
}
}
**Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.remove(ArrayList.java:492)
at CardPile.removeTop(CardPile.java:40)
at GoFish.dealCards(GoFish.java:112)
at GoFish.main(GoFish.java:13)**
编辑： 这是Player类：
public class Player {
private boolean[] books;
private CardPile pile;
private static int MAXIMUM_VALUE_CARD = 13;
public Player()
{
this.pile = new CardPile();
this.books = new boolean[13]; //by default all are false
}
public boolean hasCard(int value)
{
return this.pile.searchValue(value) > 0;
}
public Card[] removeAll(int value)
{
return this.pile.removeAll(value);
}
public void addAll(Card[] cards)
{
for (int i = 0; i < cards.length; i++)
{
this.pile.addToBottom(cards[i]);
}
}
//optional additional method
public void addCard(Card card)
{
this.pile.addToBottom(card);
}
public int getNumberCards()
{
return this.pile.getNumberCards();
}
public int countBooks()
{
int count = 0;
for (int i = 0; i < MAXIMUM_VALUE_CARD; i++)
{
if (books[i])
{
count++;
}
}
return count;
}
public void addBook(int value)
{
this.books[value - 1] = true;
}
public void printHand()
{
System.out.println("Player's hand is " + this.pile);
}
}
这是GoFish课程：
import java.util.Scanner;
public class GoFish {
private static Scanner reader;
public static void main(String[] args)
{
System.out.println("How many players?");
reader = new Scanner(System.in);
int numberPlayers = reader.nextInt();
Player[] players = createPlayersArray(numberPlayers);
int currentTurn = 0;
CardPile deck = CardPile.makeFullDeck();
dealCards(deck, players);
int maximumRetries = 2;
int numRetries = 0;
while(deck.getNumberCards() > 0 && players[currentTurn].getNumberCards() > 0)
{
updateBooks(players[currentTurn]);
if (numRetries == maximumRetries)
{
numRetries = 0;
currentTurn++;
if (currentTurn == numberPlayers)
{
currentTurn = 0;
}
}
System.out.println("Player " + currentTurn + ", here is your hand. What card would you like to ask for?");
players[currentTurn].printHand();
int queryCard = reader.nextInt();
System.out.println("And from whom would you like to get it from?");
int queryPlayer = reader.nextInt();
if (queryCard < 1 || queryCard > 13 || queryPlayer < 0 || queryPlayer >= numberPlayers || queryPlayer == currentTurn)
{
System.out.println("Invalid entries. Please retry");
numRetries++;
}
else
{
numRetries = 0;
boolean hasCard = players[queryPlayer].hasCard(queryCard);
if (hasCard)
{
System.out.println("Cards found!");
Card[] removed = players[queryPlayer].removeAll(queryCard);
players[currentTurn].addAll(removed);
}
else
{
System.out.println("Go fish!");
Card top = deck.removeTop();
System.out.println("You drew " + top);
players[currentTurn].addCard(top);
//check to make sure this extra card didn't form a book
//Note this could happen even if it doesn't match the card they were asking about
updateBooks(players[currentTurn]);
if (top.getValue() == queryCard)
{
System.out.println("You successfully went fishing!");
}
else
{
currentTurn++;
if (currentTurn == numberPlayers)
{
currentTurn = 0;
}
}
}
}
}
//calculate the winner now
int maxPlayer = 0;
int maxPlayerBooks = players[0].countBooks();
for (int i = 1; i < numberPlayers; i++)
{
int currentBooks = players[i].countBooks();
if (currentBooks > maxPlayerBooks)
{
maxPlayer = i;
maxPlayerBooks = currentBooks;
}
}
System.out.println("Congratulations! Player " + maxPlayer + " you have won the game by accumulating " + maxPlayerBooks + " books!");
}
private static Player[] createPlayersArray(int numPlayers)
{
Player[] players = new Player[numPlayers];
for (int i = 0; i < numPlayers; i++)
{
players[i] = new Player();
}
return players;
}
private static void dealCards(CardPile deck, Player[] players)
{
final int NUMBER_CARDS_PER_PLAYER = 7;
for (int i = 0; i < NUMBER_CARDS_PER_PLAYER * players.length; i++)
{
Card next = deck.removeTop();
players[i % players.length].addCard(next);
}
}
private static void updateBooks(Player player)
{
for (int i = 1; i <= 13; i++)
{
//alternative option would be to modify the hasCard method to return an int instead of boolean. Then we could just count (this is probably better design)
Card[] valued = player.removeAll(i);
if (valued.length == 4)
{
player.addBook(i);
}
else
{
player.addAll(valued);
}
}
}
}