package com.NCU.ZHANGhuirong;import java.util.ArrayList;import java.util.Collections;public class Card {  public String poker(int num) {    String str = "";    String[] face = { "♥", "♠", "♣", "♦" };    String[] number = { "A", "2", "3", "4", "5", "6", "7", "8", "9", "10",        "J", "Q", "K" };    str += face[num % 4] + number[num % 13];    return str;  }  public void shuffle(@SuppressWarnings("rawtypes") ArrayList list) {  }  @SuppressWarnings("unchecked")  public static void main(String[] args) {    @SuppressWarnings("rawtypes")    ArrayList list = new ArrayList();    Card card = new Card();    for (int i = 0; i < 52; i++) {      list.add(card.poker(i));    }    for (int i = 0; i < list.size(); i++) {      System.out.printf("%s/t", list.get(i));      if ((i + 1) % 13 == 0) {        System.out.println(" ");      }    }    System.out.println();    Collections.shuffle(list);    System.out.println("洗牌后:");    for (int i = 0; i < list.size(); i++) {      System.out.printf("%s/t", list.get(i));      if ((i + 1) % 13 == 0) {        System.out.println(" ");      }    }  }}

♥A ♠2 ♣3 ♦4 ♥5 ♠6 ♣7 ♦8 ♥9 ♠10 ♣J ♦Q ♥K  ♠A ♣2 ♦3 ♥4 ♠5 ♣6 ♦7 ♥8 ♠9 ♣10 ♦J ♥Q ♠K  ♣A ♦2 ♥3 ♠4 ♣5 ♦6 ♥7 ♠8 ♣9 ♦10 ♥J ♠Q ♣K  ♦A ♥2 ♠3 ♣4 ♦5 ♥6 ♠7 ♣8 ♦9 ♥10 ♠J ♣Q ♦K  洗牌后:♥3 ♥9 ♦6 ♥J ♦K ♥4 ♦8 ♥K ♦Q ♦5 ♣7 ♠J ♠A  ♦10 ♣A ♥8 ♠9 ♥Q ♦4 ♠6 ♠8 ♥10 ♣2 ♣10 ♦7 ♠10 ♥A ♣J ♠K ♠5 ♥2 ♣8 ♦J ♠Q ♦3 ♦9 ♣Q ♣K ♣3  ♥5 ♣6 ♣5 ♦2 ♦A ♥7 ♠4 ♥6 ♠7 ♣4 ♠3 ♠2 ♣9