对于学校项目，我创建了以下程序：
BlckJckUI.java
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class BlckJckUI {
public static void main(String args[])
{
JFrame GUI = new JFrame("Blackjack Advisor");
GUI.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
GUI.setSize(800,800);
GUI.setVisible(true);
ImageIcon Ace = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\Ace.jpg");
JButton ace = new JButton(Ace);
ace.setSize(300, 100);
ace.setLocation(100, 100);
ace.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
if (array.playerhandtotal <= 21)
{
math.cardvalue = 11;
}
else
{
math.cardvalue = 1;
}
array.clicktracker++;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(ace);
ImageIcon Two = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\2.jpg");
JButton two = new JButton(Two);
two.setSize(300, 100);
two.setLocation(100, 200);
two.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 2;
array.clicktracker++;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(two);
ImageIcon Three = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\3.jpg");
JButton three = new JButton(Three);
three.setSize(300, 100);
three.setLocation(100, 300);
three.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 3;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(three);
ImageIcon Four = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\4.jpg");
JButton four = new JButton(Four);
four.setSize(300, 100);
four.setLocation(100, 400);
four.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 4;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(four);
ImageIcon Five = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\5.jpg");
JButton five = new JButton(Five);
five.setSize(300, 100);
five.setLocation(100, 500);
five.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 5;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(five);
ImageIcon Six = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\6.jpg");
JButton six = new JButton(Six);
six.setSize(300, 100);
six.setLocation(900, 100);
six.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 6;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(six);
ImageIcon Seven = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\7.jpg");
JButton seven = new JButton(Seven);
seven.setSize(300, 100);
seven.setLocation(900, 200);
seven.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 7;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(seven);
ImageIcon Eight = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\8.jpg");
JButton eight = new JButton(Eight);
eight.setSize(300, 100);
eight.setLocation(900, 300);
eight.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 8;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(eight);
ImageIcon Nine = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\9.jpg");
JButton nine = new JButton(Nine);
nine.setSize(300, 100);
nine.setLocation(900, 400 );
nine.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 9;
array.clicktracker++;
;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(nine);
ImageIcon Ten = new ImageIcon("C:\\Users\\Hieu Vo\\workspace\\Deck-2014-01-03\\Deck\\ten.jpg");
JButton ten = new JButton(Ten);
ten.setSize(300, 100);
ten.setLocation(900, 500);
ten.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
Arrays array = new Arrays();
Math math = new Math();
math.cardvalue = 10;
array.clicktracker++;
JOptionPane.showMessageDialog(null,array.result);
}
});
GUI.add(ten);
JButton start = new JButton("Start/Reset");
start.setSize(300, 100);
start.setLocation(500,500);
start.addActionListener(new ActionListener ()
{
public void actionPerformed(ActionEvent e)
{
;
Arrays array = new Arrays();
array.playerhand.clear();
array.dealer = 0;
array.clicktracker = 0;
array.playerhandtotal = 0;
array.result = null;
JOptionPane.showMessageDialog(null,"Please select the card \nthat the dealer is showing :)");
}
});
GUI.add(start);
GUI.setLayout(null);
GUI.pack();
//start.setSize(somethinghere);
//start.setLocation(Somethinghere);
}
}
Math.java
public class Math
{
public int cardvalue;
public Math()
{
Arrays array = new Arrays();
if (array.clicktracker == 1)
{
array.dealer = cardvalue;
array.result = "Please select the first card you have :)";
}
else if (array.clicktracker == 2)
{
array.playerhand.add(cardvalue);
array.result = "Please select the second card you have :)";
}
else if (array.clicktracker >= 3)
{
array.playerhand.add(cardvalue);
if (array.playerhandtotal <= 8)
{
// array.result = result statement
array.result = "You should just hit until you're safe. If the dealer 6 or below,\n"
+ " the chances are that he'll bust and if not, remain low above 17.\n"
+ " As long as you can pull a 17 or higher, you should be safe. Pick \n"
+ "another card or reset.";
}
else if (array.playerhandtotal == 9)
{
if (3 <= array.dealer && array.dealer <= 6)
{
array.result = "Double down. The chances of him busting is high,\n"
+ "chances of him not having a high total is high as well. \n"
+ "Chances you'll get a 10 is high as well. Pick another card or reset.";
}
else
{
array.result = "Your best option is to Hit, and it's a luck thing from there. The dealer has some room with a 2; it's highly likely for him to get right below 21 and well above 16, and given that you'll have to beat him in the end, you have to hit until you're high. With 7 plus, he's set: He gets a 10 and he can stop, and again in the end, you'll have to beat his score. May the Goddess of Luck favor you, because you'll need it. Pick another card or reset.";
}
}
else if (array.playerhandtotal == 10)
{
if (2 <= array.dealer && array.dealer <= 9)
{
array.result = "Double down, since Assumption Rule wins out in your favor, if you have a 10, you're golden. The dealer has very little chance of beating you: chances are that he busts or loses to your almighty 20. Even if you bust, the chance that he busts is sufficiently high as well. Very unlikely for him to get 21. Pick another card or reset.";
}
else
{
array.result = "Hit. Dealer is in green zone, Assumption Rule states that he'll get a 20 or 21. Gotta beat him, no way around it. Hope for the best. A double will never cut it, since you're gambling on 1 card to get 20-21. Better safe than sorry. Pick another card or reset.";
}
}
else if (array.playerhandtotal == 11)
{
if (2 <= array.dealer && array.dealer <= 10)
{
array.result = "Double down, since Assumption Rule wins out in your favor, if you have a 10, you're golden. The dealer has very little chance of beating you: chances are that he busts ors loses to your almighty 21. Even if you bust, the chance that he busts is sufficiently high as well. Pick another card or reset.";
}
else
{
array.result = "Hit. He's going to have a 10 due to Assumption Rule. You may as well, but remember, you're less likely to. Thus, hit to be safe. You have to beat to win, and if you Double Down, you lock yourself into a position where the chances of you beating the dealer is slim. (At least, slimmer than hitting.) Pick another card or reset.";
}
}
else if (array.playerhandtotal == 12)
{
if ((array.dealer == 2 || array.dealer == 3) || (array.dealer >= 7))
{
array.result = "Hit. You're likely to lose anyways, per the Assumption Rule. However, there's always a chance that you won't. Doubling makes no sense, and it will reduce your chance of winning. The dealer has some room with a 2; it's highly likely for him to get right below 21 and well above 16, and given that you'll have to beat him in the end, you have to hit until you're high. With 7 plus, he's set: He gets a 10 and he can stop, and again in the end, you'll have to beat his score. Pick another card or reset.";
}
else
{
array.result = "Stand. You have a high chance of bust, but the dealer does as well. If you stay, chances are, dealer will bust. Pick another card or reset.";
}
}
else if (13 <= array.playerhandtotal && array.playerhandtotal <= 16)
{
if (array.dealer >= 7)
{
array.result = "Hit. Might as well. Chances are against you severely, but you still have to play on chance. Hitting is the safest option. Pick another card or reset.";
}
else
{
array.result = "Stand. Dealer may bust; ride on that chance. Pick another card or reset.";
}
}
else if (17 <= array.playerhandtotal && array.playerhandtotal <= 21)
{
array.result = "Stand. You're golden. Just hope for the best and let Lady Luck work her magic. Rest please.";
}
else if (array.playerhandtotal >= 22)
{
array.result = " Oi. You've busted. Reset please.";
}
}
}
}
Arrays.java
import java.util.*;
public class Arrays
{
public String result;
ArrayList<Integer> playerhand = new ArrayList<Integer>();
public int dealer = 0;
public int clicktracker = 0;
public int playerhandtotal = 0;
{
for (int element: playerhand)
{
playerhandtotal = element + playerhandtotal;
}
}
}
该程序应该是一个黑杰克咨询工具，当你点击“开始/重置”它应该要求你点击1张卡（这是经销商显示的卡。）当你点击一张卡，它然后要求你点击你拥有的第一张牌。当您点击它时，它会询问您的第二张卡等等。
当你点击开始，它工作正常，但是，当你点击任何数字卡时，JOptionPanel没有说什么。
我很确定这是因为它应该输出的字符串的值是“null”，我不希望这样。
如何使它在if-else语句中获取array.result的值？
答案 0 :(得分：0)
检查您的Arrays类。您缺少围绕for语句的方法定义。我最好的猜测是给你的结果变量一个默认的空值 - ＆gt;
public String result =“”;