RedisTemplate Hash 操作抛出异常的问题

@Service class SomeService{ private HashOperations<String, String, Integer> intHashOps;

  @Autowired
  private  RedisTemplate<String, String> redisTemplate;

  @PostConstruct
  void init(){
	hashOps = redisTemplate.opsForHash();
  }

  void do(){
    intHashOps.put("loginFailCount", username, 1);   //抛出异常
  }
}

上面的代码中，调用 do()抛出异常 java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String 这是怎么回事啊？