1. 商品详情添加Redis缓存（String类型，手动序列化）

@Resource
private StringRedisTemplate stringRedisTemplate;

@GetMapping("/{id}")
public Result queryShopById(@PathVariable("id") Long id) {
    Shop shop;
    // 1. 查询redis缓存
    String str_shop = stringRedisTemplate.opsForValue().get(CACHE_SHOP_KEY + id);
    // 2. 判断是否存在
    if (StrUtil.isNotBlank(str_shop)) {
        System.out.println("go cache " + id);
        shop = JSONUtil.toBean(str_shop, Shop.class);
        return Result.ok(shop);
    }
    // 3. 不存在从数据库查询
    shop = shopService.getById(id);
    if(shop == null) {
        return Result.fail("店铺不存在");
    }
    // 4. 在放到缓存中去
    str_shop = JSONUtil.toJsonStr(shop);
    stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, str_shop, CACHE_SHOP_TTL, TimeUnit.MINUTES);
    return Result.ok(shop);
}

<aside> 💡 反序列化对象：JSONUtil.toBean(str_shop, Shop.class); 序列化对象：JSONUtil.toJsonStr(shop);

</aside>

2. 类别添加缓存（List类型）

@GetMapping("list")
public Result queryTypeList() {
    List<ShopType> typeList;
    List<String> sList = stringRedisTemplate.opsForList().range("cache:shop-type:list", 0, -1);
    // 1. 判断缓存中是否存在
    if(!sList.isEmpty()) {
        System.out.println("go cache list");
        typeList = sList.stream().map((item) -> {
            return JSONUtil.toBean(item, ShopType.class);
        }).collect(Collectors.toList());
        return Result.ok(typeList);
    }
    // 2. 如果不存在查询MySQL
    typeList = typeService.query().orderByAsc("sort").list();
    // 3. 添加数据库
    sList = typeList.stream().map(JSONUtil::toJsonStr).collect(Collectors.toList());
    for(String s: sList) {
        stringRedisTemplate.opsForList().leftPush("cache:shop-type:list", s);
    }
    return Result.ok(typeList);
}