spring注解式缓存redis
目录
- 一、Spring整合redis
-
- 1、pom依赖
- 2、redis.properties
- 3、spring-redis.xml
- 4、applicationContext.xml
- 二、redis注解式缓存
-
- 1、**@Cacheable**
-
- ①简介
- ②ClazzBizTest
- ③ClazzBiz
- 2、@CachePut
-
- ①简介
- ②ClazzBizTest
- ③ClazzBiz
- 3、**@CacheEvict**
-
- ①简介
- ②ClazzBizTest
- ③ClazzBiz
- 三、redis击穿穿透雪崩
-
- 1、击穿
- 2、穿透
- 3、雪崩
一、Spring整合redis
1、pom依赖
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<groupId>org.examplegroupId>
<artifactId>ssm3artifactId>
<version>1.0-SNAPSHOTversion>
<packaging>warpackaging>
<name>ssm3 Maven Webappname>
<url>http://www.example.comurl>
<properties>
<project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
<maven.compiler.source>1.8maven.compiler.source>
<maven.compiler.target>1.8maven.compiler.target>
<maven.compiler.plugin.version>3.7.0maven.compiler.plugin.version>
<spring.version>5.0.2.RELEASEspring.version>
<mybatis.version>3.4.5mybatis.version>
<mysql.version>5.1.44mysql.version>
<pagehelper.version>5.1.2pagehelper.version>
<mybatis.spring.version>1.3.1mybatis.spring.version>
<commons.dbcp2.version>2.1.1commons.dbcp2.version>
<commons.pool2.version>2.4.3commons.pool2.version>
<log4j2.version>2.9.1log4j2.version>
<junit.version>4.12junit.version>
<servlet.version>4.0.0servlet.version>
<lombok.version>1.18.2lombok.version>
<ehcache.version>2.10.0ehcache.version>
<slf4j-api.version>1.7.7slf4j-api.version>
<redis.version>2.9.0redis.version>
<redis.spring.version>1.7.1.RELEASEredis.spring.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-contextartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-ormartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-txartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-aspectsartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-testartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatisartifactId>
<version>${mybatis.version}version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>${mysql.version}version>
dependency>
<dependency>
<groupId>com.github.pagehelpergroupId>
<artifactId>pagehelperartifactId>
<version>${pagehelper.version}version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatis-springartifactId>
<version>${mybatis.spring.version}version>
dependency>
<dependency>
<groupId>org.apache.commonsgroupId>
<artifactId>commons-dbcp2artifactId>
<version>${commons.dbcp2.version}version>
dependency>
<dependency>
<groupId>org.apache.commonsgroupId>
<artifactId>commons-pool2artifactId>
<version>${commons.pool2.version}version>
dependency>
<dependency>
<groupId>org.apache.logging.log4jgroupId>
<artifactId>log4j-coreartifactId>
<version>${log4j2.version}version>
dependency>
<dependency>
<groupId>org.apache.logging.log4jgroupId>
<artifactId>log4j-apiartifactId>
<version>${log4j2.version}version>
dependency>
<dependency>
<groupId>org.apache.logging.log4jgroupId>
<artifactId>log4j-webartifactId>
<version>${log4j2.version}version>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>${junit.version}version>
<scope>testscope>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>javax.servlet-apiartifactId>
<version>${servlet.version}version>
<scope>providedscope>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<version>${lombok.version}version>
<scope>providedscope>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvcartifactId>
<version>${spring.version}version>
dependency>
<dependency>
<groupId>javax.servlet.jspgroupId>
<artifactId>javax.servlet.jsp-apiartifactId>
<version>2.3.3version>
dependency>
<dependency>
<groupId>jstlgroupId>
<artifactId>jstlartifactId>
<version>1.2version>
dependency>
<dependency>
<groupId>taglibsgroupId>
<artifactId>standardartifactId>
<version>1.1.2version>
dependency>
<dependency>
<groupId>commons-fileuploadgroupId>
<artifactId>commons-fileuploadartifactId>
<version>1.3.3version>
dependency>
<dependency>
<groupId>org.hibernategroupId>
<artifactId>hibernate-validatorartifactId>
<version>6.0.7.Finalversion>
dependency>
<dependency>
<groupId>com.fasterxml.jackson.coregroupId>
<artifactId>jackson-databindartifactId>
<version>2.9.3version>
dependency>
<dependency>
<groupId>com.fasterxml.jackson.coregroupId>
<artifactId>jackson-coreartifactId>
<version>2.9.3version>
dependency>
<dependency>
<groupId>com.fasterxml.jackson.coregroupId>
<artifactId>jackson-annotationsartifactId>
<version>2.9.3version>
dependency>
<dependency>
<groupId>org.apache.shirogroupId>
<artifactId>shiro-coreartifactId>
<version>1.3.2version>
dependency>
<dependency>
<groupId>org.apache.shirogroupId>
<artifactId>shiro-webartifactId>
<version>1.3.2version>
dependency>
<dependency>
<groupId>org.apache.shirogroupId>
<artifactId>shiro-springartifactId>
<version>1.3.2version>
dependency>
<dependency>
<groupId>net.sf.ehcachegroupId>
<artifactId>ehcacheartifactId>
<version>${ehcache.version}version>
dependency>
<dependency>
<groupId>org.slf4jgroupId>
<artifactId>slf4j-apiartifactId>
<version>${slf4j-api.version}version>
dependency>
<dependency>
<groupId>org.slf4jgroupId>
<artifactId>jcl-over-slf4jartifactId>
<version>${slf4j-api.version}version>
<scope>runtimescope>
dependency>
<dependency>
<groupId>org.apache.logging.log4jgroupId>
<artifactId>log4j-slf4j-implartifactId>
<version>${log4j2.version}version>
dependency>
<dependency>
<groupId>redis.clientsgroupId>
<artifactId>jedisartifactId>
<version>${redis.version}version>
dependency>
<dependency>
<groupId>org.springframework.datagroupId>
<artifactId>spring-data-redisartifactId>
<version>${redis.spring.version}version>
dependency>
dependencies>
<build>
<finalName>ssm3finalName>
<resources>
<resource>
<directory>src/main/javadirectory>
<includes>
<include>**/*.xmlinclude>
includes>
resource>
<resource>
<directory>src/main/resourcesdirectory>
<includes>
<include>*.propertiesinclude>
<include>*.xmlinclude>
includes>
resource>
resources>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-compiler-pluginartifactId>
<version>${maven.compiler.plugin.version}version>
<configuration>
<source>${maven.compiler.source}source>
<target>${maven.compiler.target}target>
<encoding>${project.build.sourceEncoding}encoding>
configuration>
plugin>
<plugin>
<groupId>org.mybatis.generatorgroupId>
<artifactId>mybatis-generator-maven-pluginartifactId>
<version>1.3.2version>
<dependencies>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>${mysql.version}version>
dependency>
dependencies>
<configuration>
<overwrite>trueoverwrite>
configuration>
plugin>
<plugin>
<artifactId>maven-clean-pluginartifactId>
<version>3.1.0version>
plugin>
<plugin>
<artifactId>maven-resources-pluginartifactId>
<version>3.0.2version>
plugin>
<plugin>
<artifactId>maven-compiler-pluginartifactId>
<version>3.8.0version>
plugin>
<plugin>
<artifactId>maven-surefire-pluginartifactId>
<version>2.22.1version>
plugin>
<plugin>
<artifactId>maven-war-pluginartifactId>
<version>3.2.2version>
plugin>
<plugin>
<artifactId>maven-install-pluginartifactId>
<version>2.5.2version>
plugin>
<plugin>
<artifactId>maven-deploy-pluginartifactId>
<version>2.8.2version>
plugin>
plugins>
pluginManagement>
build>
project>
2、redis.properties
redis.hostName=192.168.230.128
redis.port=6379
redis.password=123456
redis.timeout=10000
redis.maxIdle=300
redis.maxTotal=1000
redis.maxWaitMillis=1000
redis.minEvictableIdleTimeMillis=300000
redis.numTestsPerEvictionRun=1024
redis.timeBetweenEvictionRunsMillis=30000
redis.testOnBorrow=true
redis.testWhileIdle=true
redis.expiration=3600
3、spring-redis.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:cache="http://www.springframework.org/schema/cache"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/cache
http://www.springframework.org/schema/cache/spring-cache.xsd">
<bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
<property name="maxIdle" value="${redis.maxIdle}"/>
<property name="maxTotal" value="${redis.maxTotal}"/>
<property name="maxWaitMillis" value="${redis.maxWaitMillis}"/>
<property name="minEvictableIdleTimeMillis" value="${redis.minEvictableIdleTimeMillis}"/>
<property name="numTestsPerEvictionRun" value="${redis.numTestsPerEvictionRun}"/>
<property name="timeBetweenEvictionRunsMillis" value="${redis.timeBetweenEvictionRunsMillis}"/>
<property name="testOnBorrow" value="${redis.testOnBorrow}"/>
<property name="testWhileIdle" value="${redis.testWhileIdle}"/>
bean>
<bean id="connectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"
destroy-method="destroy">
<property name="poolConfig" ref="poolConfig"/>
<property name="hostName" value="${redis.hostName}"/>
<property name="port" value="${redis.port}"/>
<property name="password" value="${redis.password}"/>
<property name="timeout" value="${redis.timeout}"/>
bean>
<bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">
<property name="connectionFactory" ref="connectionFactory"/>
<property name="keySerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"/>
property>
<property name="valueSerializer">
<bean class="org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer"/>
property>
<property name="hashKeySerializer">
<bean class="org.springframework.data.redis.serializer.StringRedisSerializer"/>
property>
<property name="hashValueSerializer">
<bean class="org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer"/>
property>
<property name="enableTransactionSupport" value="true"/>
bean>
<bean id="redisCacheManager" class="org.springframework.data.redis.cache.RedisCacheManager">
<constructor-arg name="redisOperations" ref="redisTemplate"/>
<property name="defaultExpiration" value="${redis.expiration}"/>
<property name="usePrefix" value="true"/>
<property name="cachePrefix">
<bean class="org.springframework.data.redis.cache.DefaultRedisCachePrefix">
<constructor-arg index="0" value="-cache-"/>
bean>
property>
bean>
<bean id="cacheKeyGenerator" class="com.zking.ssm.redis.CacheKeyGenerator">bean>
<cache:annotation-driven cache-manager="redisCacheManager" key-generator="cacheKeyGenerator"/>
beans>
4、applicationContext.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" />
<property name="ignoreResourceNotFound" value="true" />
<property name="locations">
<list>
<value>classpath:jdbc.propertiesvalue>
<value>classpath:redis.propertiesvalue>
list>
property>
bean>
<import resource="applicationContext-mybatis.xml">import>
<import resource="spring-redis.xml">import>
<import resource="applicationContext-shiro.xml">import>
beans>
二、redis注解式缓存
1、@Cacheable
①简介
配置在方法或类上，作用：本方法执行后，先去缓存看有没有数据，如果没有，从数据库中查找出来，给缓存中存一份，返回结果，
下次本方法执行，在缓存未过期情况下，先在缓存中查找，有的话直接返回，没有的话从数据库查找
value：缓存位置的一段名称，不能为空
key：缓存的key，默认为空，表示使用方法的参数类型及参数值作为key，支持SpEL
condition：触发条件，满足条件就加入缓存，默认为空，表示全部都加入缓存，支持SpEL
②ClazzBizTest
package com.zking.shiro;
import com.zking.ssm.biz.ClazzBiz;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations={"classpath:applicationContext.xml"})
public class ClazzBizTest {
@Autowired
private ClazzBiz clazzBiz;
@Test
public void test1(){
System.out.println(clazzBiz.selectByPrimaryKey(10));
System.out.println(clazzBiz.selectByPrimaryKey(10));
}
}
③ClazzBiz
package com.zking.ssm.biz;
import com.zking.ssm.model.Clazz;
import com.zking.ssm.util.PageBean;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import java.util.List;
import java.util.Map;
public interface ClazzBiz {
@CacheEvict(value = "xx",key = "'cid:'+#cid",allEntries = true)
int deleteByPrimaryKey(Integer cid);
int insert(Clazz record);
int insertSelective(Clazz record);
// xx=cache-cid:1
// key的作用改变原有的key生成规则
@Cacheable(value = "xx",key = "'cid:'+#cid",condition = "#cid > 6")
// @CachePut(value = "xx",key = "'cid:'+#cid",condition = "#cid > 6")
Clazz selectByPrimaryKey(Integer cid);
int updateByPrimaryKeySelective(Clazz record);
int updateByPrimaryKey(Clazz record);
List<Clazz> listPager(Clazz clazz, PageBean pageBean);
List<Map> listMapPager(Clazz clazz, PageBean pageBean);
}
2、@CachePut
①简介
类似于更新操作，即每次不管缓存中有没有结果，都从数据库查找结果，并将结果更新到缓存，并返回结果
value 缓存的名称，在 spring 配置文件中定义，必须指定至少一个
key 缓存的 key，可以为空，如果指定要按照 SpEL 表达式编写，如果不指定，则缺省按照方法的所有参数进行组合
condition 缓存的条件，可以为空，使用 SpEL 编写，返回 true 或者 false，只有为 true 才进行缓存
②ClazzBizTest
同第二点1、②
③ClazzBiz
@CachePut(value = "xx",key = "'cid:'+#cid",condition = "#cid > 6")
Clazz selectByPrimaryKey(Integer cid);
3、@CacheEvict
①简介
用来清除用在本方法或者类上的缓存数据（用在哪里清除哪里）
value：缓存位置的一段名称，不能为空
key：缓存的key，默认为空，表示使用方法的参数类型及参数值作为key，支持SpEL
condition：触发条件，满足条件就加入缓存，默认为空，表示全部都加入缓存，支持SpEL
allEntries：true表示清除value中的全部缓存，默认为false
②ClazzBizTest
@Test
public void test2(){
clazzBiz.deleteByPrimaryKey(10);
}
③ClazzBiz
@CacheEvict(value = "xx",key = "'cid:'+#cid",allEntries = true)
int deleteByPrimaryKey(Integer cid);
三、redis击穿穿透雪崩
1、击穿
高并发量的同时key失效，导致请求直接到达数据库；
设置锁
1.获取 Redis 锁，如果没有获取到，则回到任务队列继续排队
2.获取到锁，从数据库拉取数据并放入缓存中
3.释放锁，其他请求从缓存中拿到数据
限流：请求redis之前做流量削峰
2、穿透
很多请求都在访问数据库一定不存在的数据，造成请求将缓存和数据库都穿透的情况。
规则排除
可以增加一些参数检验。例如数据库数据 id 一般都是递增的，如果请求 id = -10 这种参数，势必绕过Redis。避免这种情况，可以对用户真实性检验等操作。
null值填充
当缓存穿透时，redis存入一个类似null的值，下次访问则直接缓存返回空，当数据库中存在该数据的值则需要把redis存在的null值清除并载入新值，此方案不能解决频繁随机不规则的key请求。
3、雪崩
雪崩和击穿类似，不同的是击穿是一个热点 Key 某时刻失效，而雪崩是大量的热点 Key 在一瞬间失效 。
给不同的热点key设置不同的缓存策略