mybatis整合redis

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。

编写Redis需要用的2个工具类   RedisUtil.java和SerializeUtil.java。这个在前一篇已经有过，这里不再重复贴代码了。

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();

1 实现类：

package app.platform.mybatis

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 redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;  

public class MybatisRedisCache implements Cache {  

    private static Logger logger = LoggerFactory.getLogger(MybatisRedisCache.class);
    private Jedis redisClient=createReids();
     /** The ReadWriteLock. */
    private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock();   

    private String id;  

    public MybatisRedisCache(final String id) {
        if (id == null) {
            throw new IllegalArgumentException("Cache instances require an ID");
        }
        logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>MybatisRedisCache:id="+id);
        this.id = id;
    }
    @Override
    public String getId() {
        return this.id;
    }  

    @Override
    public int getSize() {  

        return Integer.valueOf(redisClient.dbSize().toString());
    }  

    @Override
    public void putObject(Object key, Object value) {
        logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>putObject:"+key+"="+value);
        redisClient.set(SerializeUtil.serialize(key.toString()), SerializeUtil.serialize(value));
    }  

    @Override
    public Object getObject(Object key) {
        Object value = SerializeUtil.unserialize(redisClient.get(SerializeUtil.serialize(key.toString())));
        logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>getObject:"+key+"="+value);
        return value;
    }  

    @Override
    public Object removeObject(Object key) {
        return redisClient.expire(SerializeUtil.serialize(key.toString()),);
    }  

    @Override
    public void clear() {
          redisClient.flushDB();
    }
    @Override
    public ReadWriteLock getReadWriteLock() {
        return readWriteLock;
    }
    protected  static Jedis createReids(){
        JedisPool pool = new JedisPool(new JedisPoolConfig(), "10.12.162.85");
        return pool.getResource();
    }  

2序列化类

public class SerializeUtil {
    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;
        }  

        public static Object unserialize(byte[] bytes) {
        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;
        }  

2 spring中的mybatis配置

<!-- 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>
<!-- 开启缓存支持 -->  
<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">

<!-- 缓存 -->
  <cache eviction="LRU" type="app.platform.mybatis.MybatisRedisCache" />

<!-- 查询所有 -->
<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>

本文转自http://blog.csdn.net/fhx007/article/details/12680875 感谢作者