使用Iterator将对象添加到Hashset

 HashSet<String> set = new HashSet<String>();
 set.add("test1");
 Iterator<String> it = set.iterator();

 while(it.hasNext()){        
    it.next();        
    set.add("sf");    
    it.remove();        
 }
 HashSet<String> set = new HashSet<String>();