blocks|key|2861666|text|这意味着您的DeckOfCards类应该包含一个大小为52的数组，用于存储Card实例。您可以始终使用另一种数据结构，如链表。该数组可能应该是DeckOfCards中的私有属性，如|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2861667|private+Card+cards[]=new+Card[52];|code-block|syntax|javascript|2861668|然后用Card对象填充数组：|2861669|for(int+i=0;i<52;i%2B%2B){
++++int+cardType=i/13;
++++String+type="Heart";
++++if(cardType==0)type="Spades";
++++else+if(cardType==1)type="Clubs";
++++else+if(cardType==2)type="Diamond";
++++cards[i]=new+Card(i,+cardType);
}|2861670|同样，你最好在Stack+Overflow中询问编程问题。|2861671|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

It means that your DeckOfCards class should contain an array of size 52 that stores Card instances. You could always use another data structure like a linked list. The array should probably be a private property in DeckOfCards, like

<pre><code>private Card cards[]=new Card[52];
</code></pre>

Then you fill the array with Card object as such:

<pre><code>for(int i=0;i&lt;52;i++){
 int cardType=i/13;
 String type="Heart";
 if(cardType==0)type="Spades";
 else if(cardType==1)type="Clubs";
 else if(cardType==2)type="Diamond";
 cards[i]=new Card(i, cardType);
}
</code></pre>

Also you would probably be best off asking programming questions in Stack Overflow.

blocks|key|2650310|text|考虑这个问题的一个好方法是为类的变量(属性)赋值。即使在同一个类中有多个对象，由于您使用的是Random类，因此每个类对于这些变量都有自己的随机值。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2650311|举一个使用代码的示例，您可以有两个CardClass对象，因此它们都有cardSuit和cardNum变量，但是这两个对象的cardSuit和cardNum变量将是不同的，因为它们彼此独立，因为您将值存储到唯一的类对象中。|2650312|因此，对于您的问题，您似乎被要求将52个值(组成一副标准纸牌的值)存储到一个数组中。|2650313|entityMap^0|1A|6|0|H|9|Z|8|18|7|1Q|8|1Z|7|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|Z|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|K|$]]

A good way to think about this is you're assigning values to the variables (attributes) of a class. Even if you have multiple objects of the same class, each class will have its own random values for those variables since you're using the <code>Random</code> class. 

For an example using your code, you can have two <code>CardClass</code> objects, so they both have <code>cardSuit</code> and <code>cardNum</code> variables, but the <code>cardSuit</code> and <code>cardNum</code> variables will be different for both objects since they're independent of each other because you stored the values to the unique class objects.

So with your question, it seems like you're being asked to store 52 values (the values that make up a standard deck of cards) into an array.

blocks|key|109807|text|你可以把一个类看作是一个对象的蓝图。对象始终是类的实例。对象可以包含同一类或不同类的其他对象：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|109808|class+A+{
++++private+B+someInstanceOfB;
}|code-block|syntax|javascript|109809|现在Card类应该只包含花色(梅花、方块、黑桃和红心)、值2到10以及J、Q、K和A+(实际上，这是使用enums的理想情况，但为了简单起见，我不使用它们)。|offset|length|style|CODE|109810|Deck实际上包含52个Card对象的数组。请注意，您不能将同一张牌发两次，因此我们需要有从牌组中移除牌的可能性。ArrayList类允许我们这样做：|109811|class+Deck+{
++++private+List<Card>+cards+=+new+ArrayList<Card>;
}|109812|(您看到的尖括号是泛型的用法。您稍后会了解到这一点。现在，它指的是包含Card类型的对象的ArrayList。)|109813|现在你需要一些东西来填充数组。Robin的填充数组的方法不是很好，因为它们的值范围是从0到51。相反，您应该使用类似以下内容：|109814|class+Deck+{

++++private+List<Card>+cards+=+new+ArrayList<Card>();

++++public+Deck()+{
++++++++//+Let's+assume+that+0=clubs,+1=diamonds,+2=spades,+3=hearts
++++++++for+(int+suit+=+0;+suit+<+4;+suit%2B%2B)+{
++++++++++++//+For+each+suit,+we+add+13+cards+with+values+1+through+13.
++++++++++++for+(int+value+=+1;+value+<=+13;+value%2B%2B)+{
++++++++++++++++this.cards.add(new+Card(suit,+value));
++++++++++++}
++++++++}
++++++++//+We+did+not+yet+shuffle+the+cards,
++++++++//but+`Collections.shuffle()`+can+do+the+job.
++++}

++++public+void+dealRandom()+{
++++++++//+Pick+one+of+the+left+cards,
++++++++//+remove+it+from+the+deck
++++++++//+and+return+it.
++++}
}|109815|注意，Card类不应该洗牌，这是Deck的责任。此外，我们使用整数作为卡片类型(套装)，使用整数作为值。打印人类可读的文本来描述卡片可以委托给toString()方法。|109816|entityMap^0|0|0|2|4|1G|4|0|0|4|C|4|1L|9|0|0|Z|4|19|9|0|0|0|3|4|G|4|1Z|A|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|12|8|@$I|13|J|14|K|L]|$I|15|J|16|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|17|8|@$I|18|J|19|K|L]|$I|1A|J|1B|K|L]|$I|1C|J|1D|K|L]]|9|@]|A|$]]|$1|O|3|P|5|D|7|1E|8|@]|9|@]|A|$E|F]]|$1|Q|3|R|5|6|7|1F|8|@$I|1G|J|1H|K|L]|$I|1I|J|1J|K|L]]|9|@]|A|$]]|$1|S|3|T|5|6|7|1K|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|1L|8|@]|9|@]|A|$E|F]]|$1|W|3|X|5|6|7|1M|8|@$I|1N|J|1O|K|L]|$I|1P|J|1Q|K|L]|$I|1R|J|1S|K|L]]|9|@]|A|$]]|$1|Y|3|-4|5|6|7|1T|8|@]|9|@]|A|$]]]|Z|$]]

You might think of a class as a blueprint for an object. An object is always an instance of a class. Objects can hold other objects of the same class or of a different class:

<pre><code>class A {
 private B someInstanceOfB;
}
</code></pre>

Now the <code>Card</code> class should only contain the suit (clubs, diamonds, spades and hearts) and the value 2 through 10 and J, Q, K and A. (In fact, this is an ideal case to use <code>enum</code>s, but for simplicity, I will not use them.)

The <code>Deck</code> contains indeed an array of 52 <code>Card</code> objects. Note that you may not deal twice the same card, so we need to have the possibility to remove cards from the deck. The <code>ArrayList</code> class allows us to do so:

<pre><code>class Deck {
 private List&lt;Card&gt; cards = new ArrayList&lt;Card&gt;;
}
</code></pre>

(The angle brackets you see, is usage of Generics. You will learn about it later. For now, it means an <code>ArrayList</code> containing objects of the <code>Card</code> type.)

Now you need something to fill the array. Robin's method to fill the array is not quite good, since their values range from 0 to 51. Instead, you should use something like this:

<pre><code>class Deck {

 private List&lt;Card&gt; cards = new ArrayList&lt;Card&gt;();

 public Deck() {
 // Let's assume that 0=clubs, 1=diamonds, 2=spades, 3=hearts
 for (int suit = 0; suit &lt; 4; suit++) {
 // For each suit, we add 13 cards with values 1 through 13.
 for (int value = 1; value &lt;= 13; value++) {
 this.cards.add(new Card(suit, value));
 }
 }
 // We did not yet shuffle the cards,
 //but `Collections.shuffle()` can do the job.
 }

 public void dealRandom() {
 // Pick one of the left cards,
 // remove it from the deck
 // and return it.
 }
}
</code></pre>

Note that the <code>Card</code> class should not shuffle the cards, that's a responsability for the <code>Deck</code>. Also, we used integers as card type (suit) and integers for values. Printing a human-readable text to describe the card can be delegated to the <code>toString()</code> method.

I am working on a Java homework assignment that says:

<blockquote>
 The programming projects of Chapter 4 discussed a Card class that represents a standard playing card. Create a class called DeckofCards that stores 52 objects of the Card class. Include methods to shuffle the deck, deal a card, and report the number of cards left in the deck. The shuffle method should assume you have a full deck. Create a driver class with a main method that deals each card from a shuffled deck, printing each card as it is dealt.
</blockquote>

Where it says

<blockquote>
 Create a class called DeckofCards that stores 52 objects of the Card class.
</blockquote>

I am not sure of what that means to store something. Would it mean to create 52 objects into a class? Or, assuming that 52 objects are already made in the Card class, put all those objects in another object or constructor? I did make a card class, however, I did not make 52 objects, also there are 52 cards in a card deck so I am assuming 52 objects is the same as 52 cards. Anyways, if needed, here is the code for my card class:

<pre><code>import java.util.Random;

public class CardClass {

 private static Random generator = new Random();
 private int suit, num;
 private String cardSuit, cardNum;

 public CardClass() {
 shuffle();
 }

 public void shuffle() {
 num = generator.nextInt(13) + 1; 
 suit = generator.nextInt(4) + 1; 
 }

 public String toString() {
 if (num &gt;=2 &amp;&amp; num &lt;= 10)
 cardNum = Integer.toString(num);
 else if (num == 1)
 cardNum = "Ace";
 else if (num == 11)
 cardNum = "Jack";
 else if (num == 12)
 cardNum = "Queen";
 else 
 cardNum = "King";

 if (suit == 1)
 cardSuit = "Spades";
 else if (suit == 2)
 cardSuit = "Hearts";
 else if (suit == 3)
 cardSuit = "Clubs";
 else 
 cardSuit = "Diamonds";

 return cardNum + " of " + cardSuit; 
 }
}
</code></pre>

This is also my very first on this community so I apologize for any mistakes I made and thank you very much in advance for all your help.

What does it mean to "store" objects in a class?

数据结构

Java

我正在做一个Java作业，作业是这样写的：在第4章的编程项目中，讨论了一个表示标准扑克牌的卡片类。创建一个名为DeckofCards的类，它存储了Card类的52个对象。包括洗牌、发牌和报告牌中剩余牌的数量的方法。shuffle方法应该假设你有一个完整的卡片组。创建一个具有main方法的驱动程序类，该方法处理洗牌组中的...

问在类中“存储”对象是什么意思？
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