SSM+redis整合
ssm框架之前已经搭建过了，这里不再做代码复制工作。
这里主要是利用redis去做mybatis的二级缓存，mybaits映射文件中所有的select都会刷新已有缓存，如果不存在就会新建缓存，所有的insert，update操作都会更新缓存。
redis的好处也显而易见，可以使系统的数据访问性能更高。本节只是展示了整合方法和效果，后面会补齐redis集群、负载均衡和session共享的文章。
下面就开始整合工作：
后台首先启动redis-server（后台启动与远程连接linux服务的方法都需要改redis.conf文件），启动命令“./src/redis-server ./redis.conf”
我这里是windows系统下开发的，推荐一个可视化工具“Redis Desktop manager”,需要远程连接linux下的redis，需要linux下开启端口对外开放（具体方法是修改/etc/sysconfig/iptables文件，增加对外端口开发命令）。
以上操作都完成后，即可远程连接成功了，如图：
现在还没有缓存记录，下面进入代码阶段，首先在pom.xml中增加需要的redis jar包
<dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> <version>2.9.0</version> </dependency> <dependency> <groupId>org.springframework.data</groupId> <artifactId>spring-data-redis</artifactId> <version>1.6.2.RELEASE</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-ehcache</artifactId> <version>1.0.0</version> </dependency> <!-- 添加druid连接池包 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.24</version> </dependency>
pom.xml写好后，还需要新增两个配置文件：redis.properties
redis.host=192.168.0.109redis.port=6379redis.pass=123456redis.maxIdle=200redis.maxActive=1024redis.maxWait=10000redis.testOnBorrow=true
其中字段也都很好理解，再加入配置文件：spring-redis.xml
<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:mvc="http://www.springframework.org/schema/mvc" xmlns:util="http://www.springframework.org/schema/util" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd"> <!-- 连接池基本参数配置，类似数据库连接池 --> <context:property-placeholder location="classpath*:redis.properties" /> <bean id="poolConfig"> <property name="maxTotal" value="${redis.maxActive}"/> <property name="maxIdle" value="${redis.maxIdle}" /> <property name="testOnBorrow" value="${redis.testOnBorrow}"/> </bean> <!-- 连接池配置，类似数据库连接池 --> <bean id="jedisConnectionFactory" > <property name="hostName" value="${redis.host}"></property> <property name="port" value="${redis.port}"></property> <property name="password" value="${redis.pass}"></property> <property name="poolConfig" ref="poolConfig"></property> </bean> <!-- 调用连接池工厂配置 --> <!-- <bean id="redisTemplate"> <property name="jedisConnectionFactory" ref="jedisConnectionFactory"></property> 如果不配置Serializer，那么存储的时候智能使用String，如果用User类型存储，那么会提示错误User can't cast to String！！！ <property name="keySerializer"> <bean /> </property> <property name="valueSerializer"> <bean /> </property> </bean> --> <bean id="redisCacheTransfer"> <property name="jedisConnectionFactory" ref="jedisConnectionFactory" /> </bean></beans>配置文件写好后，就开始java代码的编写：
JedisClusterFactory.java
package com.cjl.util;import java.util.HashSet;import java.util.Properties;import java.util.Set;import java.util.regex.Pattern;import org.apache.commons.pool2.impl.GenericObjectPoolConfig;import org.springframework.beans.factory.FactoryBean;import org.springframework.beans.factory.InitializingBean;import org.springframework.core.io.Resource;import redis.clients.jedis.HostAndPort;import redis.clients.jedis.JedisCluster;public class JedisClusterFactory implements FactoryBean<JedisCluster>, InitializingBean { private Resource addressConfig; private String addressKeyPrefix; private JedisCluster jedisCluster; private Integer timeout; private Integer maxRedirections; private GenericObjectPoolConfig genericObjectPoolConfig; private Pattern p = Pattern.compile("^.+[:]//d{1,5}//s*$"); public JedisCluster getObject() throws Exception { return jedisCluster; } public Class<? extends JedisCluster> getObjectType() { return (this.jedisCluster != null ? this.jedisCluster.getClass() : JedisCluster.class); } public boolean isSingleton() { return true; } private Set<HostAndPort> parseHostAndPort() throws Exception { try { Properties prop = new Properties(); prop.load(this.addressConfig.getInputStream()); Set<HostAndPort> haps = new HashSet<HostAndPort>(); for (Object key : prop.keySet()) { if (!((String) key).startsWith(addressKeyPrefix)) { continue; } String val = (String) prop.get(key); boolean isIpPort = p.matcher(val).matches(); if (!isIpPort) { throw new IllegalArgumentException("ip 或 port 不合法"); } String[] ipAndPort = val.split(":"); HostAndPort hap = new HostAndPort(ipAndPort[0], Integer.parseInt(ipAndPort[1])); haps.add(hap); } return haps; } catch (IllegalArgumentException ex) { throw ex; } catch (Exception ex) { throw new Exception("解析 jedis 配置文件失败", ex); } } public void afterPropertiesSet() throws Exception { Set<HostAndPort> haps = this.parseHostAndPort(); jedisCluster = new JedisCluster(haps, timeout, maxRedirections, genericObjectPoolConfig); } public void setAddressConfig(Resource addressConfig) { this.addressConfig = addressConfig; } public void setTimeout(int timeout) { this.timeout = timeout; } public void setMaxRedirections(int maxRedirections) { this.maxRedirections = maxRedirections; } public void setAddressKeyPrefix(String addressKeyPrefix) { this.addressKeyPrefix = addressKeyPrefix; } public void setGenericObjectPoolConfig(GenericObjectPoolConfig genericObjectPoolConfig) { this.genericObjectPoolConfig = genericObjectPoolConfig; }}RedisCache.java
package com.cjl.util;import java.util.concurrent.locks.ReadWriteLock;import java.util.concurrent.locks.ReentrantReadWriteLock;import org.apache.ibatis.cache.Cache;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.data.redis.connection.jedis.JedisConnection;import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;import org.springframework.data.redis.serializer.JdkSerializationRedisSerializer;import org.springframework.data.redis.serializer.RedisSerializer;import redis.clients.jedis.exceptions.JedisConnectionException;public class RedisCache implements Cache { private static final Logger logger = LoggerFactory.getLogger(RedisCache.class); private static JedisConnectionFactory jedisConnectionFactory; private final String id; private final ReadWriteLock rwl = new ReentrantReadWriteLock(); public RedisCache(final String id) { if (id == null) { throw new IllegalArgumentException("Cache instances require an ID"); } logger.debug("MybatisRedisCache:id=" + id); this.id = id; } /** * 清空所有缓存 */ public void clear() { rwl.readLock().lock(); JedisConnection connection = null; try { connection = jedisConnectionFactory.getConnection(); connection.flushDb(); connection.flushAll(); } catch (JedisConnectionException e) { e.printStackTrace(); } finally { if (connection != null) { connection.close(); } rwl.readLock().unlock(); } } public String getId() { return this.id; } /** * 获取缓存总数量 */ public int getSize() { int result = 0; JedisConnection connection = null; try { connection = jedisConnectionFactory.getConnection(); result = Integer.valueOf(connection.dbSize().toString()); logger.info("添加mybaits二级缓存数量：" + result); } catch (JedisConnectionException e) { e.printStackTrace(); } finally { if (connection != null) { connection.close(); } } return result; } public void putObject(Object key, Object value) { rwl.writeLock().lock(); JedisConnection connection = null; try { connection = jedisConnectionFactory.getConnection(); RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer(); connection.set(SerializeUtil.serialize(key), SerializeUtil.serialize(value)); logger.info("添加mybaits二级缓存key=" + key + ",value=" + value); } catch (JedisConnectionException e) { e.printStackTrace(); } finally { if (connection != null) { connection.close(); } rwl.writeLock().unlock(); } } public Object getObject(Object key) { // 先从缓存中去取数据,先加上读锁 rwl.readLock().lock(); Object result = null; JedisConnection connection = null; try { connection = jedisConnectionFactory.getConnection(); RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer(); result = serializer.deserialize(connection.get(serializer.serialize(key))); logger.info("命中mybaits二级缓存,value=" + result); } catch (JedisConnectionException e) { e.printStackTrace(); } finally { if (connection != null) { connection.close(); } rwl.readLock().unlock(); } return result; } public Object removeObject(Object key) { rwl.writeLock().lock(); JedisConnection connection = null; Object result = null; try { connection = jedisConnectionFactory.getConnection(); RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer(); result = connection.expire(serializer.serialize(key), 0); } catch (JedisConnectionException e) { e.printStackTrace(); } finally { if (connection != null) { connection.close(); } rwl.writeLock().unlock(); } return result; } public static void setJedisConnectionFactory(JedisConnectionFactory jedisConnectionFactory) { RedisCache.jedisConnectionFactory = jedisConnectionFactory; } public ReadWriteLock getReadWriteLock() { // TODO Auto-generated method stub return rwl; }}RedisCacheTransfer.java
package com.cjl.util;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;/** * 静态注入中间类 */public class RedisCacheTransfer { @Autowired public void setJedisConnectionFactory(JedisConnectionFactory jedisConnectionFactory) { RedisCache.setJedisConnectionFactory(jedisConnectionFactory); }}SerializeUtil.java
package com.cjl.util;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;/** * * @author cjl * */public class SerializeUtil { /** * 序列化 */ public static byte[] serialize(Object object) { ObjectOutputStream oos = null; ByteArrayOutputStream baos = null; try { // 序列化 baos = new ByteArrayOutputStream(); oos = new ObjectOutputStream(baos); oos.writeObject(object); byte[] bytes = baos.toByteArray(); return bytes; } catch (Exception e) { e.printStackTrace(); } return null; } /** *反序列化 */ public static Object unserialize(byte[] bytes) { if (bytes !=null) { ByteArrayInputStream bais = null; try { // 反序列化 bais = new ByteArrayInputStream(bytes); ObjectInputStream ois = new ObjectInputStream(bais); return ois.readObject(); } catch (Exception e) { } } return null; }}所有东西准备齐全后还需要修改映射文件
要使mybaits缓存生效，还需如上图这样开启二级缓存。配置文件还需要在web.xml中加载生效
一切准备就绪后，启动服务
启动成功后，点击员工表单可以触发查询所有员工的方法，第一次进行查询语句可以看到mybatis打印了查询语句，并在redis服务器中更新了一条缓存
我们清空控制台再次点击查询员工按钮执行查询方法，可以看到没有执行查询语句，证明第二次查询直接从缓存中取值，没有连接mysql进行查询。
总结
以上所述是小编给大家介绍的redis与ssm整合方法（mybatis二级缓存），希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对武林网网站的支持！