使用java实现洗牌

static String[] pokers = new String[54];
public static void randomSet(int min, int max, int n, HashSet<Integer> set) {
if (n > (max - min + 1) || max < min) {
return;
}
for (int i = 0; i < n; i++) {
// 调用Math.random()方法
int num = (int) (Math.random() * (max - min)) + min;
set.add(num);// 将不同的数存入HashSet中
}
int setSize = set.size();
// 如果存入的数小于指定生成的个数，则调用递归再生成剩余个数的随机数，如此循环，直到达到指定大小
if (setSize < n) {
randomSet(min, max, n - setSize, set);// 递归
}
}
public static void main(String []args)throws Exception{
//1.定义花色数组
String[] colors = {"红桃","黑桃","梅花","方片"};
//2.定义牌面数组
String[] numbers = {"A","2","3","4","5","6","7","8","9","10","J","Q","K"};
//3.定义王
String[] kings = {"大王","小王"};

//4.使用循环将牌存储到pokers数组
int index = 0;
for(int i = 0 ; i < numbers.length ; i ++) {
for(int j = 0 ; j < colors.length ; j ++) {
pokers[index ++] = colors[j] + numbers[i];
}
}

//将大小王加入扑克数组
System.arraycopy(kings, 0, pokers, index, 2);
HashSet<Integer> set = new HashSet<Integer>();
randomSet(0,100000,54,set);
for (int j : set) {
}
List<Integer>list = new ArrayList<>();
for (Integer str : set) {
list.add(str);
}
Map<String, String>map = new TreeMap<>();
//循环遍历扑克数组，将这个扑克的牌加入map，生成随机数让他们顺序不一样
for(int i = 0 ;i<pokers.length;i++){
map.put(list.get(i)+"", pokers[i]);
}

Map<String, String> resultMap = MapSortDemo.sortMapByKey(map); //按Key进行排序
for (Map.Entry<String, String> entry : resultMap.entrySet()) {
System.out.println( entry.getValue());
}

 

 

 

/**
* 使用 Map按key进行排序
* @param map
* @return
*/
public static Map<String, String> sortMapByKey(Map<String, String> map) {
if (map == null || map.isEmpty()) {
return null;
}

Map<String, String> sortMap = new TreeMap<String, String>(
new MapKeyComparator());

sortMap.putAll(map);

return sortMap;
}
}

 

class MapKeyComparator implements Comparator<String>{

@Override
public int compare(String str1, String str2) {

return str1.compareTo(str2);
}
}

 

后来发现貌似还有一种更简单的方法，直接使用collections的shuffle方法 打乱list集合里面的数据 就可以了 但是没有经过测试