spring整合redis缓存，以注解(@Cacheable、@CachePut、@CacheEvict)形式使用

maven项目中在pom.xml中依赖2个jar包，其他的spring的jar包省略：

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<dependency>

<groupId>redis.clients</groupId>

<artifactId>jedis</artifactId>

<version>2.8.1</version>

</dependency>

<dependency>

<groupId>org.springframework.data</groupId>

<artifactId>spring-data-redis</artifactId>

<version>1.7.2.RELEASE</version>

</dependency>

spring-Redis.xml中的内容：

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<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"

xmlns:context="http://www.springframework.org/schema/context"

xmlns:mvc="http://www.springframework.org/schema/mvc"

xmlns:cache="http://www.springframework.org/schema/cache"

xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache-4.2.xsd">
<context:property-placeholder location="classpath:redis-config.properties" />

<!-- 启用缓存注解功能，这个是必须的，否则注解不会生效，另外，该注解一定要声明在spring主配置文件中才会生效 -->

<cache:annotation-driven cache-manager="cacheManager" />

<!-- redis 相关配置 -->

<bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">

<property name="maxIdle" value="${redis.maxIdle}" />

<property name="maxWaitMillis" value="${redis.maxWait}" />

<property name="testOnBorrow" value="${redis.testOnBorrow}" />

</bean>

<bean id="JedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"

p:host-name="${redis.host}" p:port="${redis.port}" p:password="${redis.pass}" p:pool-config-ref="poolConfig"/>

<bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">

<property name="connectionFactory" ref="JedisConnectionFactory" />

</bean>

<!-- spring自己的缓存管理器，这里定义了缓存位置名称 ，即注解中的value -->

<bean id="cacheManager" class="org.springframework.cache.support.SimpleCacheManager">

<property name="caches">

<set>

<!-- 这里可以配置多个redis -->

<!-- <bean class="com.cn.util.RedisCache">

<property name="redisTemplate" ref="redisTemplate" />

<property name="name" value="default"/>

</bean> -->

<bean class="com.cn.util.RedisCache">

<property name="redisTemplate" ref="redisTemplate" />

<property name="name" value="common"/>

<!-- common名称要在类或方法的注解中使用 -->

</bean>

</set>

</property>

</bean>

</beans>

redis-config.properties中的内容：

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# Redis settings

# server IP

redis.host=127.0.0.1

# server port

redis.port=6379

# server pass

redis.pass=

# use dbIndex

redis.database=0

# 控制一个pool最多有多少个状态为idle(空闲的)的jedis实例

redis.maxIdle=300

# 表示当borrow(引入)一个jedis实例时，最大的等待时间，如果超过等待时间(毫秒)，则直接抛出JedisConnectionException；

redis.maxWait=3000

# 在borrow一个jedis实例时，是否提前进行validate操作；如果为true，则得到的jedis实例均是可用的

redis.testOnBorrow=true

com.cn.util.RedisCache类中的内容：

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package com.cn.util;

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import org.springframework.cache.Cache;

import org.springframework.cache.support.SimpleValueWrapper;

import org.springframework.dao.DataAccessException;

import org.springframework.data.redis.connection.RedisConnection;

import org.springframework.data.redis.core.RedisCallback;

import org.springframework.data.redis.core.RedisTemplate;

public class RedisCache implements Cache{

private RedisTemplate<String, Object> redisTemplate;

private String name;

public RedisTemplate<String, Object> getRedisTemplate() {

return redisTemplate;

}

public void setRedisTemplate(RedisTemplate<String, Object> redisTemplate) {

this.redisTemplate = redisTemplate;

}

public void setName(String name) {

this.name = name;

}

@Override

public String getName() {

// TODO Auto-generated method stub

return this.name;

}

@Override

public Object getNativeCache() {

// TODO Auto-generated method stub

return this.redisTemplate;

}

@Override

public ValueWrapper get(Object key) {

// TODO Auto-generated method stub

System.out.println("get key");

final String keyf = key.toString();

Object object = null;

object = redisTemplate.execute(new RedisCallback<Object>() {

public Object doInRedis(RedisConnection connection)

throws DataAccessException {

byte[] key = keyf.getBytes();

byte[] value = connection.get(key);

if (value == null) {

return null;

}

return toObject(value);

}

});

return (object != null ? new SimpleValueWrapper(object) : null);

}

@Override

public void put(Object key, Object value) {

// TODO Auto-generated method stub

System.out.println("put key");

final String keyf = key.toString();

final Object valuef = value;

final long liveTime = 86400;

redisTemplate.execute(new RedisCallback<Long>() {

public Long doInRedis(RedisConnection connection)

throws DataAccessException {

byte[] keyb = keyf.getBytes();

byte[] valueb = toByteArray(valuef);

connection.set(keyb, valueb);

if (liveTime > 0) {

connection.expire(keyb, liveTime);

}

return 1L;

}

});

}

private byte[] toByteArray(Object obj) {

byte[] bytes = null;

ByteArrayOutputStream bos = new ByteArrayOutputStream();

try {

ObjectOutputStream oos = new ObjectOutputStream(bos);

oos.writeObject(obj);

oos.flush();

bytes = bos.toByteArray();

oos.close();

bos.close();

}catch (IOException ex) {

ex.printStackTrace();

}

return bytes;

}

private Object toObject(byte[] bytes) {

Object obj = null;

try {

ByteArrayInputStream bis = new ByteArrayInputStream(bytes);

ObjectInputStream ois = new ObjectInputStream(bis);

obj = ois.readObject();

ois.close();

bis.close();

} catch (IOException ex) {

ex.printStackTrace();

} catch (ClassNotFoundException ex) {

ex.printStackTrace();

}

return obj;

}

@Override

public void evict(Object key) {

// TODO Auto-generated method stub

System.out.println("del key");

final String keyf = key.toString();

redisTemplate.execute(new RedisCallback<Long>() {

public Long doInRedis(RedisConnection connection)

throws DataAccessException {

return connection.del(keyf.getBytes());

}

});

}

@Override

public void clear() {

// TODO Auto-generated method stub

System.out.println("clear key");

redisTemplate.execute(new RedisCallback<String>() {

public String doInRedis(RedisConnection connection)

throws DataAccessException {

connection.flushDb();

return "ok";

}

});

}

@Override

public <T> T get(Object key, Class<T> type) {

// TODO Auto-generated method stub

return null;

}

@Override

public ValueWrapper putIfAbsent(Object key, Object value) {

// TODO Auto-generated method stub

return null;

}

}

到了这一步，大部分人会想在web.xml的启动配置文件地方(context-param)加入了spring-redis.xml,让项目启动时加载这个配置文件吧，但是这样启动后注解不生效。

正确的做法是：web.xml中配置了servlet控制器：

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<servlet>

<servlet-name>SpringMVC</servlet-name>

<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

<init-param>

<param-name>contextConfigLocation</param-name>

<param-value>/WEB-INF/spring-mvc.xml</param-value>

</init-param>

<load-on-startup>1</load-on-startup>

<async-supported>true</async-supported>

</servlet>

在DispatcherServlet的初始化过程中，框架会在web应用的 WEB-INF文件夹下寻找名为spring-mvc.xml的配置文件，如果不指定的话，默认是applicationContext.xml

只需要在spring-mvc.xml文件中引入spring-redis配置文件即可，正如spring-redis.xml中的启用注解说的：<cache:annotation-driven cache-manager="cacheManager" />注解一定要声明在spring主配置文件中才会生效。

spring-mvc.xml内容，省略了spring与spring MVC整合的那部分：

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<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"

xmlns:context="http://www.springframework.org/schema/context"

xmlns:mvc="http://www.springframework.org/schema/mvc"

xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd">
<!-- 自动扫描该包，使SpringMVC认为包下用了@controller注解的类是控制器 -->

<context:component-scan base-package="com.cn" />

<!-- 引入同文件夹下的redis属性配置文件 -->

<import resource="spring-redis.xml"/>

</beans>

在service的实现类中：

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@Service

public class UserServiceImpl implements UserService{

@Autowired

private UserBo userBo;

@Cacheable(value="common",key="'id_'+#id")

public User selectByPrimaryKey(Integer id) {

return userBo.selectByPrimaryKey(id);

}

@CachePut(value="common",key="#user.getUserName()")

public void insertSelective(User user) {

userBo.insertSelective(user);

}

@CacheEvict(value="common",key="'id_'+#id")

public void deleteByPrimaryKey(Integer id) {

userBo.deleteByPrimaryKey(id);

}

}