N个任务掌握java系列之统计一篇文章中单词出现的次数

import java.util.HashMap;
import java.util.Iterator;

public class Has {
  // 统计单词出现的次数
    public static String StatList(String str) {
   StringBuffer sb = new StringBuffer();
   HashMap<String ,Integer> has = new HashMap<String ,Integer> (); // 打开一个哈希表
   String[] slist = str.split(" ");
   for (int i = 0; i < slist.length; i++) {
         if (!has.containsKey(slist[i])) { // 若尚无此单词
                 has.put(slist[i], 1);
         } else {//如果有，就在将次数加1
        	 	Integer nCounts = has.get(slist[i]);
                 has.put(slist[i],nCounts+1 );
        }
     }
//遍历map
     Iterator iterator = has.keySet().iterator();
      while(iterator.hasNext()){
             String word = (String) iterator.next();
             sb.append("单词：").append(word).append(" 次数").append(has.get(word)).append("\n");
      }
      return sb.toString();
}
 
public static void main(String[] args) {
        String s = new String("You are the mananger of an office supplies company. A colleague has received a letter compaining about an order for office furniture. She has left the letter for you to answer and has written some notes on it.");
        System.out.println(StatList(s));
}
}