遍历hashmap的三种方式_HashMap

 public static void main(String[] args) { 
   
        Map<String,String> map = new HashMap();
        map.put("aa","11");
        map.put("bb","22");
        Set<String> set = map.keySet();
        Iterator iter = set.iterator();
        while(iter.hasNext()){ 
   
            System.out.println(iter.next());
        }
    }