1、redis的具体安装就不说了，直接连接程序，配置在项目test002中，依赖

<!-- redis数据存储 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <!-- JSON处理器 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.70</version>
        </dependency>

2、配置yml

spring:
  profiles:
    active: dev
  datasource:      #配置数据库
    driverClassName: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3307/springcloud_test002?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
    username: root
    password: root
  redis:
    host: 192.168.110.12
    port: 6379
    password: Cc68db0e

 3、配置redis公共类

package com.example.test002.mapper.common;


import com.alibaba.fastjson.JSON;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.concurrent.TimeUnit;

@Component
public class RedisMapper {

    private StringRedisTemplate stringRedisTemplate;
    @Resource
    public void RedisMapper(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    /**
     * 判断key是否存在
     * @param key 键
     * @return true 存在 false不存在
     */
    public boolean hasKey(String folder, String key) {
        try {
            return stringRedisTemplate.hasKey(folder + key);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }

    /**
     * 功能描述: 普通缓存放入，全部对象都以JSON保存
     * @param folder, key, value
     * @return boolean true成功 false失败
     * @author admin
     * @date 2021/7/19 11:03
     * @update [序号] [时间] [修改人] [自定义变更内容]
     */
    public boolean set(String folder, String key, Object value) {
        try {
            String json = JSON.toJSONString(value);
            stringRedisTemplate.opsForValue().set(folder + key, json);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }

    /**
     * 普通缓存获取
     * @param key 键
     * @return 值
     */
    public String get(String folder, String key) {
        return key == null ? null : stringRedisTemplate.opsForValue().get(folder + key);
    }


    /**
     * 普通缓存放入并设置时间
     * @param key   键
     * @param value 值
     * @param time  时间(秒) time要大于0 如果time小于等于0 将设置无限期
     * @return true成功 false 失败
     */
    public boolean set(String folder, String key, Object value, long time) {
        try {
            String json = JSON.toJSONString(value);
            if (time > 0) {
                stringRedisTemplate.opsForValue().set(folder + key, json, time, TimeUnit.SECONDS);
            } else {
                stringRedisTemplate.opsForValue().set(folder + key, json, 36000, TimeUnit.SECONDS);
            }
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }


}

4、编写方法测试

package com.example.test002.controller;


import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.example.test002.entity.SysUserDO;
import com.example.test002.mapper.SysUserMapper;
import com.example.test002.mapper.common.RedisMapper;
import org.apache.tomcat.jni.User;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import java.util.List;
import java.util.Map;


/**
 * redis 测试
 * @author admin
 * @date 2022/2/10 9:47
 */
@RestController
@RefreshScope               //nacos配置中心动态刷新
public class RedisController {

    @Resource
    private RedisMapper redisMapper;

    /**
     * 功能描述: 判断redis中是否存在这个key
     * @author admin
     * @return boolean
     * @date 2022/2/10 13:30
     */
    @GetMapping(value = "/redis/hasKey")
    public boolean hasKey() throws InterruptedException {
        String folder = "xxxTest:";
        String key = "aaaaa";

        boolean hasKey = redisMapper.hasKey(folder, key);
        return hasKey;
    }

    /**
     * 功能描述: redis存储值
     * @author admin
     * @return boolean
     * @date 2022/2/10 13:30
     */
    @GetMapping(value = "/redis/set")
    public boolean set() throws InterruptedException {
        String folder = "xxxTest:";
        String key = "aaaaa";
        SysUserDO user = new SysUserDO();
        user.setId(111);
        user.setRolename("测试数据");
        boolean set = redisMapper.set(folder, key, user);
        return set;
    }

    /**
     * 功能描述: redis获取值
     * @author admin
     * @return boolean
     * @date 2022/2/10 13:30
     */
    @GetMapping(value = "/redis/get")
    public SysUserDO get() throws InterruptedException {
        String folder = "xxxTest:";
        String key = "aaaaa";
        SysUserDO sysUserDO = JSON.parseObject(redisMapper.get(folder, key), new TypeReference<SysUserDO>() {
        });
        return sysUserDO;
    }




}

访问接口，都能成功