不确定是否需要编辑此课程，因为卡片正在更改。只是不按顺序
import java.lang.Integer;
/**
* This class is used to keep track of playing cards.
*
* @author (name)
* @version (date)
*/
public class Card implements Comparable<Card>
{
public int compareTo(Card otherCard) {
// instance variables - replace the example below with your own
private String denom, suit;
/**
* Card is to be passed in as a denomination and suit
*/
public Card(String description)
{
description = description.toUpperCase();
if( description.length() == 2)
{
suit = description.substring(1);
denom = description.substring(0,1);
} else if(description.length() == 3) {
suit = description.substring(2);
denom = description.substring(0,2);
} else {
System.out.print("Error: An invalid card code was given.");
}
}
/**
* This will give a string that states a description of the card.
* @return Card description as a string.
*/
public String getDis()
{
//get the description
String denomMessage = denom;
if(denom.equals("A"))
denomMessage = "Ace";
else if(denom.equals("K"))
denomMessage = "King";
else if(denom.equals("Q"))
denomMessage = "Queen";
else if(denom.equals("J"))
denomMessage = "Jack";
//get the suit
String suitMessage = suit;
if(suit.equals("S"))
suitMessage = "Spades";
else if(suit.equals("D"))
suitMessage = "Dimonds";
else if(suit.equals("C"))
suitMessage = "Clubs";
else if(suit.equals("H"))
suitMessage = "Hearts";
else
suitMessage = "There was a problem";
return denomMessage + " of " + suitMessage;
}
/**
* This was written for the purpose of helping to select a card image.
* @return clubs are 1, hearts are 2, spades are 3, diamonds are 4
*/
public int numSuit()
{
int value = 0;
if(suit.equals("C"))
value = 1;
else if(suit.equals("H"))
value = 2;
else if(suit.equals("S"))
value = 3;
else if(suit.equals("D"))
value = 4;
return value;
}
/**
* This class was written for the purpose of selecting a card image
* @return ace is a 1, jack is a 11, queen is a 12, king is a 13
*/
public int numDenom()
{
int value = 0;
if(denom.equals("A"))
value = 1;
else if(denom.equals("J"))
value = 11;
else if(denom.equals("Q"))
value = 12;
else if(denom.equals("K"))
value = 13;
else
value = Integer.parseInt(denom);
return value;
}
/**
* Are the two cards the same suit and denomination?
* @return true or false
*/
public boolean equals(Card a)
{
if(denom.equals(a.denom) && suit.equals(a.suit))
return true;
else
return false;
}
/**
* I would suggest that you write this method
*/
public int denomCompareTo(Card a)
{
return a.numDenom() - numDenom();
}
}
它正在做的就是将它的卡更改为输入的最低卡。我必须按顺序从最小到最大。无论面对什么。
import java.awt.*;
import java.io.*;
import java.applet.*;
import java.awt.image.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
/**
* This applet is currently working. It will run in a webpage. It will take in card codes such as
* 2h for the two of heart and "paint" the image of five cards when all five text fields each have a
* card coding entered into them. Your assignment will be to write the part of the code
* that will sort the cards once they have been entered so that the will be "painted" from smallest
* to largest denomination regardless of suit as long "None" is selected in the drop down box. In
* the event one of the suits is selected that suit will be placed in order first then followed by
* the rest of the cards in order. To complete the assignment you should read through this class' code
* but you will only need to change the section that state that you should change it and possibly
* the card class.
*
* @author (Put your name here.)
* @version (Put the date here.)
*/
public class CardApplet extends Applet {
Image ic1,ic2,ic3,ic4,ic5;
Card c1,c2,c3,c4,c5;
private TextField cardIn1,cardIn2,cardIn3,cardIn4,cardIn5;
private String message;
private Button enter,sort;
private ButtonListener buttonListen;
private Choice trump;
static final int CARD_WIDTH = 73;
static final int CARD_HEIGHT = 98;
/**
* This is called an inner class as it is a class writen inside of another class. It is here so
* that the buttons will be able to trigger an event.
*/
class ButtonListener implements ActionListener
{
/**
* The name of this method is important and should not be changed. This will take in the
* "action" of a button being pushed and store reference to it in the object variable e.
*/
public void actionPerformed(ActionEvent e)
{
String action = e.paramString();
if( action.indexOf("Enter") >= 0)
{
//get text
String text1 = cardIn1.getText();
String text2 = cardIn2.getText();
String text3 = cardIn3.getText();
String text4 = cardIn4.getText();
String text5 = cardIn5.getText();
//Get rid of whitespace before and after string
text1 = text1.trim();
text2 = text2.trim();
text3 = text3.trim();
text4 = text4.trim();
text5 = text5.trim();
message = "Cards Entered";
//setup cards and card images
c1 = new Card(text1);
ic1 = getCardImage(c1);
c2 = new Card(text2);
ic2 = getCardImage(c2);
c3 = new Card(text3);
ic3 = getCardImage(c3);
c4 = new Card(text4);
ic4 = getCardImage(c4);
c5 = new Card(text5);
ic5 = getCardImage(c5);
//this method call is to this class and tells the applet to follow the code of paint again.
repaint();
}
else if( action.indexOf("Sort") >= 0)
{
//ADD YOUR CODE HERE.
if(c1.denomCompareTo(c2) < 0 )
ic1 = ic2;
c1 = c2;
if(c1.denomCompareTo(c3) < 0 )
ic1 = ic3;
c1 = c3;
if(c1.denomCompareTo(c4) < 0 )
ic1 = ic4;
c1 = c4;
if(c1.denomCompareTo(c5) < 0 )
ic1 = ic5;
c1 = c5;
if(c2.denomCompareTo(c1) < 0 )
ic2 = ic1;
c2 = c1;
if(c2.denomCompareTo(c3) < 0 )
ic2 = ic3;
c2 = c3;
if(c2.denomCompareTo(c4) < 0 )
ic2 = ic4;
c2 = c4;
if(c2.denomCompareTo(c5) < 0 )
ic2 = ic5;
c2 = c5;
if(c3.denomCompareTo(c1) < 0 )
ic3 = ic1;
c3 = c1;
if(c3.denomCompareTo(c2) < 0 )
ic3 = ic2;
c3 = c2;
if(c3.denomCompareTo(c4) < 0 )
ic3 = ic4;
c3 = c4;
if(c3.denomCompareTo(c5) < 0 )
ic3 = ic5;
c3 = c5;
if(c4.denomCompareTo(c1) < 0 )
ic4 = ic1;
c4 = c1;
if(c4.denomCompareTo(c2) < 0 )
ic4 = ic2;
c4 = c2;
if(c4.denomCompareTo(c3) < 0 )
ic4 = ic3;
c4= c3;
if(c4.denomCompareTo(c5) < 0 )
ic4 = ic5;
c4 = c5;
if(c5.denomCompareTo(c1) < 0 )
ic5 = ic1;
c5 = c1;
if(c5.denomCompareTo(c2) < 0 )
ic5 = ic2;
c5 = c2;
if(c5.denomCompareTo(c3) < 0 )
ic5 = ic3;
c5 = c3;
if(c5.denomCompareTo(c4) < 0 )
ic5 = ic4;
c5 = c4;
//DO NOT CHANGE CODE PAST THIS LINE.
message = "Sorted";
repaint();
}
}
} //end of inner class.
/**
* This method is called when the applet is first started. It will setup the layout of the applet.
*/
public void init() {
//This is the text that prints in the gray box towards the bottem of the applet.
message="Let us get started ";
//Sets the back ground color of the the applet
setBackground(Color.GREEN);
// Set default layout manager
setLayout(new FlowLayout() );
//setup textboxes for entering in cards
cardIn1 = new TextField("Enter",4);
add(cardIn1);
cardIn2 = new TextField("cards ",4);
add(cardIn2);
cardIn3 = new TextField("using",4);
add(cardIn3);
cardIn4 = new TextField("Chap 5",4);
add(cardIn4);
cardIn5 = new TextField("coding",4);
add(cardIn5);
//place buttons
buttonListen = new ButtonListener();
enter = new Button("Enter");
enter.addActionListener(buttonListen);
add(enter);
sort = new Button("Sort");
sort.addActionListener(buttonListen);
add(sort);
//setup dropdown
trump = new Choice();
trump.addItem("None");
trump.addItem("Hearts");
trump.addItem("Diamonds");
trump.addItem("Spades");
trump.addItem("Clubs");
add(trump);
//Since the card object variables are null each image object variable
//will hold reference to a card back image.
ic1 = getCardImage(c1);
ic2 = getCardImage(c2);
ic3 = getCardImage(c3);
ic4 = getCardImage(c4);
ic5 = getCardImage(c5);
}
/*
* This class is used to place graphics on an applet.
*/
public void paint(Graphics g) {
//places cards on applet
int linePos = 70;
g.drawImage(ic1,19,linePos,this);
g.drawImage(ic2,19+CARD_WIDTH,linePos,this);
g.drawImage(ic3,19+2*CARD_WIDTH,linePos,this);
g.drawImage(ic4,19+3*CARD_WIDTH,linePos,this);
g.drawImage(ic5,19+4*CARD_WIDTH,linePos,this);
// simple text displayed on applet
g.setColor(Color.lightGray);
g.draw3DRect(2, 175, 200, 20, true);
g.fillRect(2, 175, 200, 20);
g.setColor(Color.black);
g.drawString(message, 4, 190);
}
/**
* This will select either the correct portion of the cards image based on the suit and denomination or
* the card back image.
* @param a The card object holds the suit and denomination in state.
* @return It returns an image object variable with holds reference to a image that was created for a card that was passed in.
* @throws MalformedURLException
*/
public Image getCardImage(final Card a)
{
int cardDenom,cardSuit;
Image playingCards = null;
ImageFilter cardFilter;
ImageProducer cardProducer;
if( a == null)
{
playingCards = getImage(getCodeBase(), "cardBack.png");
}else{
playingCards = getImage(getCodeBase(),"cards.png");
cardDenom = (a.numDenom()*CARD_WIDTH)- CARD_WIDTH;
cardSuit = (a.numSuit()*CARD_HEIGHT) - CARD_HEIGHT;
cardFilter = new CropImageFilter(cardDenom,cardSuit,CARD_WIDTH,CARD_HEIGHT);
cardProducer = new FilteredImageSource(playingCards.getSource(),cardFilter);
playingCards = createImage(cardProducer);
}
return playingCards;
}
}
答案 0 :(得分：1)
在提及可比较
时，提示是正确的来自http://docs.oracle.com/javase/6/docs/api/java/lang/Comparable.html
将此对象与指定的订单对象进行比较。返回负整数，零或正整数，因为此对象小于，等于或大于指定对象。
这意味着您的对象（卡片）的Comparable实现应遵循该约定。
在您的热门代码部分
public int denomCompareTo(Card a)
{
if ( a.numDenom() < this.numDenom() ) //the value of card a is less
{ return -1; }
else if ( a.numDenom() == this.numDenom() ) //equality
{ return 0; }
else //otherwise.. whatever's left (a must be greater)
{ return 1;}
}
阅读它，直到你理解为止。可比较的是你想要肯定的方法。它将通过调用
来调用FirstCard.CompareTo( SecondCard );
该代码行将返回-1,0或1的值。取决于哪个更大，如果它们相等则为0。这就是所有排序算法真正/需要/能够找出排序。
这就是Comparable所需的代码。在你理解之前请仔细检查。
第二部分中的代码，
else if( action.indexOf("Sort") >= 0)
{
//ADD YOUR CODE HERE.
...
}
需要更新以反映可比较的工作方式。
所以我猜这是一个按钮或动作的东西，如果你指定排序，那么我们想要对卡片进行排序。很公平。那么，卡存放在哪里？它看起来像是一堆名为c（number）和ic（number）的变量。像c1和ic1，c2和ic2。将来，请研究使用数组。
所以你的代码几乎是正确的！这只是你需要一个临时值来存储旧卡。否则你每次都会覆盖它。
例如：第一个篮子是苹果，第二个篮子是葡萄。
如果你说“嘿，把第二个篮子的内容放到第一个篮子里”，那么第一个篮子就变成了葡萄。第二个也是（仍然）葡萄。苹果去哪了？我们失去了它，因为计算机对你的指示毫不含糊。我们需要将旧卡存储在一个新变量中。
所以当你说
时if(c1.denomCompareTo(c2) < 0 ) { //for the love of jobe please use braces for multiline if statements
ic1 = ic2;
c1 = c2;
}
原来的ic1和c1被覆盖并丢失。
你可以通过使用临时变量或交换变量来解决这个问题，或者当你变得非常聪明时，使用XOR（问你的书呆子朋友）
Image tempImg;
Card tempCard;
if(c1.denomCompareTo(c2) < 0 ) { //meaning if card1 is less than card2
tempImg = ic1; //store card1 temporarily
tempCard = c1;
ic1 = ic2; //copy vals of card2 to card1 slots
c1 = c2;
ic2 = tempImg; //slide the original val of ic1 here
c2 = tempCard;
}
当然，您的排序算法是准确的，但如果卡片有任何时髦的排序，则需要多次通过。这就是为什么你可能需要多次循环这些指令。你正在逐步做一些通常被称为“冒泡排序”的事情...如果你需要帮助循环你的排序，请告诉我们。
以下是一些例子：
我发布了一个非常快速的参考示例供您查看。但是，要理解它并不难，一旦你理解了它，事情就会变得容易一些。
import java.util。*;
enum Suit {
HEART,
DIAMOND,
CLUB,
SPADE
}
class Card implements Comparable<Card> {
private int rank;
private Suit suit;
public Card ( int rank, Suit suit ) {
this.rank = rank;
this.suit = suit;
}
public int getRank () {
return rank;
}
public void setRank ( int rank ) {
this.rank = rank;
}
public Suit getSuit () {
return suit;
}
public void setSuit ( Suit suit ) {
this.suit = suit;
}
@Override
public int compareTo ( Card anotherCard ) {
return this.rank - anotherCard.rank;
}
@Override
public String toString () {
return String.format ("Suit: %8s Rank: %8s", suit, rank);
}
}
public class CardsExample {
private static final int TOTAL_CARDS = 52;
private static final int CARDS_PER_SUIT = 13;
private static final int TOTAL_SUITS = 4;
private List<Card> deck;
public CardsExample () {
deck = new ArrayList<Card> ();
}
private void createDeck () {
for ( Suit suit : Suit.values () ) {
for ( int i = 0; i < CARDS_PER_SUIT; ++i ) {
deck.add ( new Card ( i, suit ) );
}
}
}
private void displayDeck () {
for ( Card card : deck ) {
System.out.println ( card );
}
}
private void performTask () {
createDeck ();
Collections.shuffle ( deck );
System.out.println ( "Before SORTING" );
displayDeck ();
Collections.sort ( deck );
System.out.println ( "After SORTING" );
displayDeck ();
}
public static void main ( String[] args ) {
new CardsExample ().performTask ();
}
}
修改
如果想要按照Suit首先对卡进行排序，那么也可以使用Comparator，在此示例中，不需要进行太多更改，只需更改{ {1}}部分，如下所示，并在enum类中提供Comparator < Card >的实施，让Card完成工作，如本例所示。
Collections.sort ( deck, suitComparator )