话不多说直接开始：
首先，引入 maven依赖：

<!--        redis依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

yml 文件：
这里有 mysql 和 redis 的，需要写上host，端口，密码和默认数据库

spring:
  redis:
    host: 8.140.xx.xxx
    port: 6379
    database: 0
    password: xxxx
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://8.xxxxx55/qingxxxxxxxxmuity?useUnicode=true&characterEncoding=utf8&serverTimezone=GMT%2B8
    username: roxxxxx
    password: Txxxxxx

开始编写redis的配置类：

@Component
@EnableCaching
@EnableAutoConfiguration
@Configuration
public class RedisConfig extends CachingConfigurerSupport  {
    private static final long DEFAULT_TTL = 999999L;
    @Value("${spring.redis.host}")
    private String host;

    @Value("${spring.redis.port}")
    private int port;

    @Value("${spring.redis.database}")
    private int database;

    @Value("${spring.redis.password}")
    private String password;

    /**
     * 连接redis的工厂类
     * @return
     */
    @Bean
    public JedisConnectionFactory jedisConnectionFactory() {
        JedisConnectionFactory factory = new JedisConnectionFactory();
        factory.setHostName(host);
        factory.setPort(port);
        factory.setPassword(password);
        factory.setDatabase(database);
        return factory;
    }

    /**
     * 配置RedisTemplate
     * 设置添加序列化器
     * key 使用string序列化器
     * value 使用Json序列化器
     * 还有一种简答的设置方式，改变defaultSerializer对象的实现。
     * @return
     */
    @Bean
    public RedisTemplate<String, Object> redisTemplate() {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        RedisSerializer stringSerializer = new StringRedisSerializer();//序列化为String
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);//序列化为Json
        template.setKeySerializer(stringSerializer);
        template.setValueSerializer(jackson2JsonRedisSerializer);
        template.setHashKeySerializer(stringSerializer);
        template.setHashValueSerializer(jackson2JsonRedisSerializer);
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);

        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
        //set value serializer
        template.setDefaultSerializer(jackson2JsonRedisSerializer);

        template.setConnectionFactory(jedisConnectionFactory());
        template.afterPropertiesSet();
        return template;
    }

    @Bean
    public CacheManager cacheManager(RedisConnectionFactory redisConnectionFactory) {
        //初始化一个RedisCacheWriter
        RedisCacheWriter redisCacheWriter = RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory);
        //自定义key前缀
        CacheKeyPrefix cacheKeyPrefix = new CacheKeyPrefix() {
            @Override
            public String compute(String cacheName) {
                return cacheName+":";
            }
        };
        //设置CacheManager的值序列化方式为json序列化
        RedisSerializer<Object> jsonSerializer = new GenericJackson2JsonRedisSerializer();
        RedisSerializationContext.SerializationPair<Object> pair = RedisSerializationContext.SerializationPair
                .fromSerializer(jsonSerializer);
        //生成RedisCacheConfiguration配置
        RedisCacheConfiguration defaultCacheConfig = RedisCacheConfiguration.defaultCacheConfig()
                .computePrefixWith(cacheKeyPrefix)
                .serializeValuesWith(pair);
        //设置默认超过期时间是30秒
        defaultCacheConfig.entryTtl(Duration.ofSeconds(DEFAULT_TTL));
        //初始化RedisCacheManager
        return new RedisCacheManager(redisCacheWriter, defaultCacheConfig);
    }
    

}

配置类整合好，建立一个 redis 的工具类：（便于操作）

package com.community.util;

/**
 * @Classname RedisUtil
 * @Description redis工具类
 * @Date 2021/10/10 16:15
 * @Created by thx
 */

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.Collection;
import java.util.concurrent.TimeUnit;

/**
 * @ClassName RedisUtil
 * @Description TODO
 * @Author 华达州
 * @Date 2021/8/6 13:54
 * @Version 1.0
 **/
@Component
public class RedisUtil {
    @Autowired
    private RedisTemplate redisTemplate;
    
    public Object get(String key) {
        return key == null ? null : redisTemplate.opsForValue().get(key);
    }


    /**
     * 本来只可以放入string类型，但是配置了自动序列化所以这儿可以传入object
     */
    public boolean set(String key, Object value) {
        try {
            redisTemplate.opsForValue().set(key, value);
            return true;
        } catch (Exception e) {
            return false;
        }
    }

    /**
     * 原子操作
     *
     * @param key
     * @param value
     * @param expire 过期时间 秒
     * @return
     */
    public boolean setExpire(String key, Object value, long expire) {
        try {
            //TimeUnit.SECONDS指定类型为秒
            redisTemplate.opsForValue().set(key, value, expire, TimeUnit.SECONDS);
            return true;
        } catch (Exception e) {
            return false;
        }
    }

    /**
     * 非原子操作
     *
     * @param key
     * @param expire
     * @return
     */
    public boolean expire(String key, long expire) {
        try {
            redisTemplate.expire(key, expire, TimeUnit.SECONDS);
            return true;
        } catch (Exception e) {
            return false;
        }
    }

    /**
     * @param key
     * @return 获取key的过期时间
     */
    public long ttl(String key) {
        return redisTemplate.getExpire(key);
    }

    /**
     * @param keys 删除key 可变参数
     */
    public void del(String... keys) {
        if (keys != null && keys.length > 0) {
            redisTemplate.delete((Collection<String>) CollectionUtils.arrayToList(keys));
        }
    }

    /**
     * @param key
     * @param step 传入正数 就是加多少 传入负数就是减多少
     * @return
     */
    public long incrBy(String key, long step) {
        return redisTemplate.opsForValue().increment(key, step);
    }

    /**
     * @param key
     * @param value
     * @return 如果该key存在就返回false 设置不成功 key不存在就返回ture设置成功
     * 如果不存在的话再 set，如果存在，不改变值:
     */
    public boolean setNx(String key, Object value) {
        return redisTemplate.opsForValue().setIfAbsent(key, value);
    }

    /**
     * 原子操作
     *
     * @param key
     * @param value
     * @param expire 在上面方法加上过期时间设置
     * @return
     */
    public boolean setNxAndExpire(String key, Object value, long expire) {
        return redisTemplate.opsForValue().setIfAbsent(key, value, expire, TimeUnit.SECONDS);
    }


    /**
     * @param key
     * @return 判断key是否存在
     */
    public boolean hasKey(String key) {
        return redisTemplate.hasKey(key);
    }
}

配置完成，开始测试！
在 controller 层里写一个 demo 进行测试

@Resource
    private RedisUtil redisUtil;
    
@RequestMapping("demo")
    public ResultJson test() {
        redisUtil.set("thx", "123");
        System.out.println(redisUtil.get("thx"));
        return null;
    }

去 redis 查看数据，如果发现有 thx 的键值，说明测试成功，完成闭环