public byte[] get(byte[] key) {
    // 使用了lambda表达式
    return redisTemplate.execute((RedisConnection redisConnection) -> redisConnection.get(key));
}

public byte[] get(byte[] key) {
    return redisTemplate.execute(new RedisCallback<byte[]>() {
        @Override
        public byte[] doInRedis(RedisConnection redisConnection) throws DataAccessException {
            // 传入byte[]类型的key，获取byte[]类型的value
            byte[] bytes = redisConnection.get(key);
            return bytes;
        }
    });
}