mybatis整合redis重写生成key的方法

来源：互联网发布：dts hd mac 编辑：程序博客网时间：2024/06/03 11:16

   mybatis默认缓存是PerpetualCache，可以查看一下它的源码，发现其是Cache接口的实现；那么我们的缓存只要实现该接口即可。
   该接口有以下方法需要实现：
String getId();
int getSize();
void putObject(Object key, Object value);
Object getObject(Object key);
Object removeObject(Object key);
void clear();
ReadWriteLock getReadWriteLock();
下面是mybatis整合redis，做数据查询的语句结果缓存，我们通过mybatis redis整合实现代码和配置了解它们的技术实现：
1 实现类：
   MybatisRedisCache.java

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    packageapp.platform.mybatis
 
    importjava.util.concurrent.locks.ReadWriteLock;  
    importjava.util.concurrent.locks.ReentrantReadWriteLock;  
       
    importorg.apache.ibatis.cache.Cache;  
    importorg.slf4j.Logger;  
    importorg.slf4j.LoggerFactory;  
       
    importredis.clients.jedis.Jedis;  
    importredis.clients.jedis.JedisPool;  
    importredis.clients.jedis.JedisPoolConfig;  
       
/**
 * redis 整合mybatis Cache实现类
 *
 * <a href="http://www.zyiqibook.com">在一起 学习交流分享网 IT技术分享</a>
 */
    publicclass MybatisRedisCacheimplements Cache { 
           
        privatestatic Logger logger = LoggerFactory.getLogger(MybatisRedisCache.class); 
        privateJedis redisClient=createReids();  
         /** The ReadWriteLock. */   
        privatefinal ReadWriteLock readWriteLock =new ReentrantReadWriteLock();  
           
        privateString id;  
           
        publicMybatisRedisCache(finalString id) {    
            if(id == null) { 
                thrownew IllegalArgumentException("Cache instances require an ID"); 
            } 
            logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>MybatisRedisCache:id="+id); 
            this.id = id; 
        }   
        @Override 
        publicString getId() {  
            returnthis.id;  
        } 
       
        @Override 
        publicint getSize() {  
          
            returnInteger.valueOf(redisClient.dbSize().toString());  
        } 
       
        @Override 
        publicvoid putObject(Object key, Object value) { 
            logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>putObject:"+key+"="+value); 
            redisClient.set(SerializeUtil.serialize(key.toString()), SerializeUtil.serialize(value)); 
        } 
       
        @Override 
        publicObject getObject(Object key) {  
            Object value = SerializeUtil.unserialize(redisClient.get(SerializeUtil.serialize(key.toString()))); 
            logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>getObject:"+key+"="+value); 
            returnvalue;  
        } 
       
        @Override 
        publicObject removeObject(Object key) {  
            returnredisClient.expire(SerializeUtil.serialize(key.toString()),0); 
        } 
       
        @Override 
        publicvoid clear() {  
              redisClient.flushDB(); 
        } 
        @Override 
        publicReadWriteLock getReadWriteLock() {  
            returnreadWriteLock;  
        } 
        protected static Jedis createReids(){ 
            JedisPool pool =new JedisPool(newJedisPoolConfig(), "10.12.162.85"); 
            returnpool.getResource();  
        }
   }

SerializeUtil.java

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/**
 * redis 整合mybatis 序列化工具类
 *
 * <a href="http://www.zyiqibook.com">在一起 学习交流分享网 IT技术分享</a>
 */
    publicclass SerializeUtil { 
        publicstatic 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(); 
            returnbytes;  
            }catch (Exception e) { 
             e.printStackTrace(); 
            } 
            returnnull;  
        } 
                
        publicstatic Object unserialize(byte[] bytes) { 
            ByteArrayInputStream bais =null;  
            try{  
            //反序列化 
            bais =new ByteArrayInputStream(bytes); 
            ObjectInputStream ois =new ObjectInputStream(bais); 
            returnois.readObject();  
            }catch (Exception e) { 
                
            } 
            returnnull;  
        } 
    }

2 spring中的mybatis配置

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="mapperLocations" value="classpath*:app/mapper/**/*.xml"/>
        <property name="configLocation" value="classpath:/mybatis/mybatis-config.xml" />
</bean>
3 mybatis-config.xml 中的settings配制
<settings>

<setting name="cacheEnabled" value="true" />
.......
</settings>
4 在需要加缓存的sqlMap中加入<cache eviction="LRU" type="app.platform.mybatis.MybatisRedisCache" />
例：
<mapper namespace="SYS_ROLE">

<cache eviction="LRU" type="app.platform.mybatis.MybatisRedisCache" />
   
<select id="findAll" parameterType="HashMap" resultType="HashMap">
    select
       <include refid="base_column" />
    from SYS_ROLE
    where 1=1
    <if test="BUS_TYPE!=null and BUS_TYPE!=''">
       and BUS_TYPE =#{BUS_TYPE}
    </if>
    <if test="ENABLE!=null and ENABLE!=''">
       and ENABLE =#{ENABLE}
    </if>
    <if test="ROLE_NAME!=null and ROLE_NAME!=''">
       and ROLE_NAME like '%'||#{ROLE_NAME}||'%'
    </if>
    <if test="ROLE_OTHER_NAME!=null and ROLE_OTHER_NAME!=''">
       and ROLE_OTHER_NAME like '%'||#{ROLE_OTHER_NAME}||'%'
    </if>
</select>
</mapper>
在项目中，我们可以检测到，首次查询是有语句打印，第二次则直接从redis缓存中获取。

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mybatis整合redis重写 生成key的方法

mybatis整合redis重写生成key的方法