引入redis依赖

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

 修改项目启动类，增加注解@EnableCaching，开启缓存功能 

application.yml中配置Redis连接信息，如下：

redis:
  database: 0
  host: 127.0.0.1
  port: 6379
  password:
  jedis:
    pool:
    # 最大空闲连接
      max-idle: 8
      # 最小空闲链接
      min-idle: 0
      # 最大连接数（负数表示没有限制）
      max-active: 8
  # 链接超时时间（毫秒）
  timeout: 5

新建Redis缓存配置类RedisConfig

package com.example.demo.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.cache.RedisCacheWriter;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.time.Duration;


/**
 * Redis缓存配置类
 *
 * @author szekinwin
 */
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {

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

    //缓存管理器
    @Bean
    public CacheManager cacheManager(RedisConnectionFactory redisConnectionFactory) {
        RedisCacheConfiguration redisCacheConfiguration = RedisCacheConfiguration
.defaultCacheConfig()
.entryTtl(Duration.ofHours(1)); // 设置缓存有效期一小时
        return RedisCacheManager .builder(RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory))
                .cacheDefaults(redisCacheConfiguration)
                .build();
    }

    @Bean
    public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory factory) {
        StringRedisTemplate template = new StringRedisTemplate(factory);
        setSerializer(template);//设置序列化工具
        template.afterPropertiesSet();
        return template;
    }

    private void setSerializer(StringRedisTemplate template) {
        @SuppressWarnings({"rawtypes", "unchecked"})
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        template.setValueSerializer(jackson2JsonRedisSerializer);
    }
}
注：springboot2.x中，RedisCacheManager已经没有了单参数的构造方法 

Soringboot1.x版本
   //缓存管理器     
@Bean      
public CacheManager cacheManager(@SuppressWarnings("rawtypes")RedisTemplate redisTemplate) {         RedisCacheManager cacheManager = new RedisCacheManager(redisTemplate);         //设置缓存过期时间          
cacheManager.setDefaultExpiration(10000);         
return cacheManager;     
} 

在相应的Mapper上使用@CacheConfig(cacheNames = "XXXX")注解

@Select("select * from sms_system")
public List<System> systemList();

/**
 * 根据ID获取系统信息
 * @param id
 * @return
 */
@Select("select * from sms_system where id=#{id}")
@Cacheable(key ="#p0")
public System getByid(@Param("id") String id);

//如果指定为 true，则方法调用后将立即清空所有缓存
@CacheEvict(key ="#p0",allEntries=true)
@Delete("delete from sms_system where id=#{id}")
void deleteById(@Param("id")String id);

　@Cacheable将查询结果缓存到redis中，（key="#p0"）指定传入的第一个参数作为redis的key。

　　@CachePut，指定key，将更新的结果同步到redis中

　　@CacheEvict，指定key，删除缓存数据，allEntries=true,方法调用后将立即清除缓存