所以我用你的建议(Todd Hopp)重写了它,并更新了BlackJack课程中(*)部分的帖子,这样你就可以看到我现在如何拥有它,但我仍然得到了同样的结果错误,它不会出于某种原因打印computePlayerValue ....
错误: 线程" main"中的例外情况java.lang.NumberFormatException:对于输入字符串:" King" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at BlackJack.dealCards(BlackJack.java:25)
at PlayCardGame.main(PlayCardGame.java:9)
P.S。我试图在书中查一下但是找不到答案...... BlackJack类是本书前一章的部分源代码,我无法弄清楚是否有必要有super();在构造函数那里?我认为只有在父类构造函数有参数时才需要这样做?如果它必须在那里,任何帮助,如果是这样的话。
BlackJack Class
public class BlackJack extends CardGameFP{
int computePlayerValue;
int computeDealerValue;
int cardValue;
public BlackJack() {
**super();**
player1 = 2;
player2 = 2;
}
public void display() {
System.out.println("BlackJack");
}
//*************************************************************
public int getCardValue(Card card) {
final String rank = card.getRank();
switch (rank) {
case "Ace":
return 1;
case "King":
case "Queen":
case "Jack":
return 10;
default:
return Integer.parseInt(rank);
}
}
public void dealCards() {
//Player 1
System.out.println("Player 1:");
for(int x = 0; x < playerHand; x++) {
shuffle();
System.out.println(fullDeck[x].getRank() + " of " + fullDeck[x].getSuit());
}
cardValue1 = getCardValue(fullDeck[0]);
cardValue2 = getCardValue(fullDeck[1]);
computePlayerValue = cardValue1 + cardValue2;
System.out.println(computePlayerValue);
}
//*************************************************************
//Dealer hand
System.out.println("\nPlayer 2:");
for(int x = 0; x < player2; x++) {
System.out.println(fullDeck[x].getRank() + " of " + fullDeck[x].getSuit() );
shuffle();
}
}
}
public class Card {
protected String suit;
protected int value;
protected String rank;
protected final int LOW_VALUE = 1;
protected final int HIGH_VALUE = 13;
public String getRank() {
return rank;
}
public int getValue() {
return value;
}
public String getSuit() {
return suit;
}
public void setSuit(String st) {
suit = st;
}
public void setValue(int val) {
if(val >= LOW_VALUE && val <= HIGH_VALUE) {
value = val;
}
else {
value = LOW_VALUE;
}
if(val == 1) {
rank = "Ace";
}
else if(val == 11) {
rank = "Jack";
}
else if(val == 12) {
rank = "Queen";
}
else if(val == 13) {
rank = "King";
}
else {
rank = Integer.toString(value);
}
}
}
CardGame Class
abstract public class CardGameFP {
int suitNum = 1;
int val = 1;
int player1;
int player2;
protected final int DECK_OF_CARDS = 52;
Card fullDeck[] = new Card[DECK_OF_CARDS];
protected final int LOW_VALUE = 1;
protected final int HIGH_VALUE = 13;
protected final int HIGH_SUIT = 4;
protected final int CARDS_IN_SUIT = 13;
public abstract void display();
public abstract void dealCards();
public CardGameFP() {
for(int i = 0; i < fullDeck.length; i++) {
fullDeck[i] = new Card();
if(suitNum == 1) {
fullDeck[i].setSuit("Spades");
}
else if(suitNum == 2) {
fullDeck[i].setSuit("Hearts");
}
else if(suitNum == 3) {
fullDeck[i].setSuit("Diamonds");
}
else {
fullDeck[i].setSuit("Clubs");
}
fullDeck[i].setValue(val);
val++;
if(val > HIGH_VALUE) {
suitNum++;
val = 1;
}
}//end for
}
public void shuffle() {
for(int firstCard = 0; firstCard < DECK_OF_CARDS; firstCard++ ) {
firstCard = ((int)(Math.random() * 500) % DECK_OF_CARDS);
int secondCard = ((int)(Math.random() * 500) % DECK_OF_CARDS);
Card temp = fullDeck[firstCard];
fullDeck[firstCard] = fullDeck[secondCard];
fullDeck[secondCard] = temp;
}
}
}
PlayCardGame Class
PlayerCardGame
public class PlayCardGame {
public static void main(String[] args) {
Card CG = new Card();
BlackJack BJ = new BlackJack();
BJ.display();
BJ.dealCards();
}
}
答案 0 :(得分:2)
而不是这一行:
cardValue = Integer.parseInt(fullDeck[0].getRank());
我建议你创建一个getCardValue(Card)
方法:
public int getCardValue(Card card) {
final String rank = card.getRank();
switch (rank) {
case "Ace":
return 1;
case "King":
case "Queen":
case "Jack":
return 10;
default:
return Integer.parseInt(rank);
}
}
然后使用:
cardValue = getCardValue(fullDeck[0]);
编辑:根据@WorldSEnder的建议,您可以定义Rank
枚举:
public enum Rank {
ACE("Ace", 1),
TWO("2", 2),
...
QUEEN("Queen", 10),
KING("King", 10);
private final String displayName;
private final int value;
protected Rank(String displayName, int value) {
this.displayName = displayName;
this.value = value;
}
public String displayName() {
return displayName;
}
public int value() {
return value;
}
}
然后,您可以修改Card
以使用Rank
代替String
作为排名并使用:
cardValue = fullDeck[0].getRank().value();
答案 1 :(得分:1)
致电时:
cardValue = Integer.parseInt(fullDeck[0].getRank());
方法Interger.parseInt()
正在尝试从int
读取string
。问题是某些卡片的排名本身不是King
之类的字符串。因此,当您返回该卡的排名时,parseInt()
不知道如何处理King
。您应该使用fullDeck[0].getVaule()
获取卡的实际值,然后解析它。它将是1到13之间的字符串。