如何使用注解实现Redis缓存功能
c语言编写的key,value存储系统(区别于MySQL的二维表格的形式存储。)
rdb:周期性的持久化
aof:以日志形式追加
默认rdb开启,同时开启使用aof
数据类型:string、list、set、zset、hash、
bitMaps 字节形式存储、geospatial 经纬度类型...
单线程:采用多路io复用实现高并发
使用:
添加依赖
<!-- redis --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <!-- spring2.X集成redis所需common-pool2--> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> <version>2.6.0</version> </dependency>登录后复制
创建配置类 固定写法
package com.lzq.yygh.common; import com.fasterxml.jackson.annotation.JsonAutoDetect; import com.fasterxml.jackson.annotation.PropertyAccessor; import com.fasterxml.jackson.databind.ObjectMapper; import org.springframework.cache.CacheManager; 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.connection.RedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer; import org.springframework.data.redis.serializer.RedisSerializationContext; import org.springframework.data.redis.serializer.RedisSerializer; import org.springframework.data.redis.serializer.StringRedisSerializer; import java.net.UnknownHostException; import java.time.Duration; @Configuration @EnableCaching //开启缓存功能 public class RedisConfig { /** * 设置RedisTemplate规则 * @param redisConnectionFactory * @return */ @Bean public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory)throws UnknownHostException { RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>(); redisTemplate.setConnectionFactory(redisConnectionFactory); Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class); //解决查询缓存转换异常的问题 ObjectMapper om = new ObjectMapper(); // 指定要序列化的域,field,get和set,以及修饰符范围,ANY是都有包括private和public om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY); // 指定序列化输入的类型,类必须是非final修饰的,final修饰的类,比如String,Integer等 om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); jackson2JsonRedisSerializer.setObjectMapper(om); //序列号key value redisTemplate.setKeySerializer(new StringRedisSerializer()); redisTemplate.setValueSerializer(jackson2JsonRedisSerializer); redisTemplate.setHashKeySerializer(new StringRedisSerializer()); redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer); redisTemplate.afterPropertiesSet(); return redisTemplate; } /** * 设置CacheManager缓存规则 * @param factory * @return */ @Bean public CacheManager cacheManager(RedisConnectionFactory factory) { RedisSerializer<String> redisSerializer = new StringRedisSerializer(); Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class); //解决查询缓存转换异常的问题 ObjectMapper om = new ObjectMapper(); om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY); om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); jackson2JsonRedisSerializer.setObjectMapper(om); // 配置序列化(解决乱码的问题),过期时间600秒 RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig() .entryTtl(Duration.ofSeconds(600)) //缓存过期10分钟 ---- 业务需求。 .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))//设置key的序列化方式 .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer)) //设置value的序列化 .disableCachingNullValues(); RedisCacheManager cacheManager = RedisCacheManager.builder(factory) .cacheDefaults(config) .build(); return cacheManager; } }登录后复制
添加配置信息
spring.redis.host=127.0.0.1 spring.redis.port=6379 spring.redis.database= 0 spring.redis.timeout=1800000 spring.redis.lettuce.pool.max-active=20 spring.redis.lettuce.pool.max-wait=-1 #最大阻塞等待时间(负数表示没限制) spring.redis.lettuce.pool.max-idle=5 spring.redis.lettuce.pool.min-idle=0登录后复制
使用注解实现功能
缓存@Cacheable
根据方法对其返回结果进行缓存,下次请求时,如果缓存存在,则直接读取缓存数据返 回;如果缓存不存在,则执行方法,并把返回的结果存入缓存中。一般用在查询方法 上。
缓存@CachePut
每次执行带有此注解标记的方法时,结果都将被存储在指定的缓存中。可以直接从响应缓存中读取数据,不必再访问数据库。一般用在新增方法上。
缓存@CacheEvict
使用该注解标志的方法,会清空指定的缓存。一般用在更新或者删除方法上
在返回serviceimpl中标注注解 没设置key时会自动加上参数作为key
@Cacheable(value = "dict", key = "'selectIndexList'+#id")