/**
 * 通过使用redis默认的序列化获取String类型的值
 *
 * @param key 键
 * @return String类型的值
 */
public String getStringBySer(String key) {
    try {
        return (String) redisTemplate.execute((RedisCallback<String>) connection -> {
            RedisSerializer<String> serializer = redisTemplate.getStringSerializer();
            byte[] serialize = serializer.serialize(key);
            if (serialize == null) {
                return null;
            }
            byte[] value = connection.get(serialize);
            return serializer.deserialize(value);
        });
    } catch (Exception e) {
        return null;
    }
}