Java 产生不重复的随机数

  int numberCount = 6;  Set set = new TreeSet();  while (set.size() < numberCount) {   int number = (int) (Math.random() * 33)+1;   if (!set.contains(number)) {    set.add(number);   }  }// out.println(set); String result=set.toString().substring(1,set.toString().length()-1);// result=result.lastIndexOf(",");// out.println(result);for(int i=0;i<set.size();i++){//Iterator ite=ts.iterator();}int team=Integer.parseInt(request.getParameter("team"));   String[] str=(String[])request.getSession().getAttribute("fnstr");   for(int i=0;i<str.length;i++){   out.println(str[i]);   }