redis与ssm整合方法（mybatis二级缓存）

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=192.168.0.109
redis.port=6379
redis.pass=123456
redis.maxidle=200
redis.maxactive=1024
redis.maxwait=10000
redis.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" class="redis.clients.jedis.jedispoolconfig">
    <property name="maxtotal" value="${redis.maxactive}"/>
    <property name="maxidle" value="${redis.maxidle}" />
    <property name="testonborrow" value="${redis.testonborrow}"/>
  </bean>
  <!-- 连接池配置，类似数据库连接池 -->
  <bean id="jedisconnectionfactory" class="org.springframework.data.redis.connection.jedis.jedisconnectionfactory" >
    <property name="hostname" value="${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" class=" org.springframework.data.redis.core.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
      class="org.springframework.data.redis.serializer.stringredisserializer" />
    </property>
    <property name="valueserializer">
      <bean
        class="org.springframework.data.redis.serializer.jdkserializationredisserializer" />
    </property>
  </bean> -->
  <bean id="rediscachetransfer" class="com.cjl.util.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服务器之家网站的支持！

原文链接：http://www.cnblogs.com/cuijiale/p/8012008.html