code: @Override
  	public boolean delete() {
          for (CallbackListener callbackListener : this.callbackListeners) {
              callbackListener.beforeDelete(this);
          }
  		boolean ret = super.delete();
  		if (this.syncToRedis && ret) {
  			//delete from Redis
  			this.redis().del(this.redisKey(this));
  		}
          for (CallbackListener callbackListener : this.callbackListeners) {
              callbackListener.afterDelete(this);
          }
  		return ret;
  	}
docs: delete from db, if `syncToRedis` is true , this model will delete from redis in the same time.