黑马点评系列问题之P37商户点评缓存作业，用了string和list两种方法，可以直接复制粘贴

 为了保持所有代码的装逼性，我们先在RedisContants这个类里面添加一个常量。后面会用。

用String类型的方法

controller

    @GetMapping("list")
    public Result queryTypeList() {
        return typeService.queryTypeList();
    }

ShopTypeServiceImpl

package com.hmdp.service.impl;
import cn.hutool.core.collection.CollectionUtil;
import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.hmdp.dto.Result;
import com.hmdp.entity.ShopType;
import com.hmdp.mapper.ShopTypeMapper;
import com.hmdp.service.IShopTypeService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
import java.util.List;
import static com.hmdp.utils.RedisConstants.SHOP_LIST_KEY;
@Service
public class ShopTypeServiceImpl extends ServiceImpl<ShopTypeMapper, ShopType> implements IShopTypeService {
    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Override
    public Result queryTypeList() {

        String shopListJson = stringRedisTemplate.opsForValue().get(SHOP_LIST_KEY);
        if (StrUtil.isNotBlank(shopListJson)) {
            List<ShopType> shopTypeList = JSONUtil.toList(shopListJson, ShopType.class);
            return Result.ok(shopTypeList);
        }
        List<ShopType> shopTypeList = query().orderByAsc("sort").list();
        if (CollectionUtil.isEmpty(shopTypeList)) {
            return Result.fail("出错了，数据不存在");
        }
        String jsonStr = JSONUtil.toJsonStr(shopTypeList);
        stringRedisTemplate.opsForValue().set(SHOP_LIST_KEY, jsonStr);
        return Result.ok(shopTypeList);
    }
}

用list类型的方法

（前面都一样）。将对应部分给他提换掉就可以了。

@Resource
    private StringRedisTemplate stringRedisTemplate;
    @Override
    public Result queryTypeList() {

        List<String> shopTypeList = stringRedisTemplate.opsForList().range(SHOP_LIST_KEY, 0, -1);
        if(CollectionUtil.isNotEmpty(shopTypeList)){
            List<ShopType> list = JSONUtil.toList(shopTypeList.get(0), ShopType.class);
            return Result.ok(list);
        }
        List<ShopType> typeList = query().orderByAsc("sort").list();
        if(CollectionUtil.isEmpty(typeList)){
            return Result.fail("列表信息不存在");
        }
        String jsonStr = JSONUtil.toJsonStr(typeList);
        stringRedisTemplate.opsForList().leftPushAll(SHOP_LIST_KEY, jsonStr);
        return Result.ok(typeList);
    }