卡洗牌和交易。

import java.security.SecureRandom;

public class Main

{

   // execute application/**from N o  w  J a v a . c o m - 时  代  Java**/

   public static void main(String[] args)

   {

      DeckOfCards myDeckOfCards = new DeckOfCards();

      myDeckOfCards.shuffle(); // place Cards in random order

      

      // print all 52 Cards in the order in which they are dealt

      for (int i = 1; i <= 52; i++)

      {

         // deal and display a Card

         System.out.printf("%-19s", myDeckOfCards.dealCard());


     if (i % 4 == 0) // output a newline after every fourth card

        System.out.println();

      } 
      /**
      来 自 N o w J a v a . c o m - 时代Java
      **/

   } 

}


class Card 

{

   private final String face; // face of card ("Ace", "Deuce", ...)

   private final String suit; // suit of card ("Hearts", "Diamonds", ...)


   // two-argument constructor initializes card's face and suit

   public Card(String face, String suit)

   {

      this.face = face;

      this.suit = suit; 

   } 


   // return String representation of Card

   public String toString() 

   { 

      return face + " of " + suit;

   } 

}

class DeckOfCards

{

   private Card[] deck; // array of Card objects

   private int currentCard; // index of next Card to be dealt (0-51)

   private static final int NUMBER_OF_CARDS = 52; // constant # of Cards

   // random number generator

   private static final SecureRandom randomNumbers = new SecureRandom();


   // constructor fills deck of Cards

   public DeckOfCards()

   {

      String[] faces = {"Ace", "Deuce", "Three", "Four", "Five", "Six", 

         "Seven", "Eight", "Nine", "Ten", "Jack", "Queen", "King"};

      String[] suits = {"Hearts", "Diamonds", "Clubs", "Spades"};


      deck = new Card[NUMBER_OF_CARDS]; // create array of Card objects

      currentCard = 0; // first Card dealt will be deck[0]


      // populate deck with Card objects

      for (int count = 0; count < deck.length; count++) 

         deck[count] = 

            new Card(faces[count % 13], suits[count / 13]);

   } 


   public void shuffle()