mybatis整合redis

升木

     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();
1、实现Cache接口

import com.sf.sfbuy.utils.SerializeUtil;
import org.apache.ibatis.cache.Cache;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
public class RedisCache implements Cache {
private final String id;
private Jedis redisClient;
private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock();
private Jedis createReids() {
JedisPoolConfig poolConfig = new JedisPoolConfig();
JedisPool pool = new JedisPool(poolConfig, "10.122.66.166");
try {
return pool.getResource();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public RedisCache(String id) {
this.id = id;
if (redisClient == null) {
redisClient = createReids();
}
}
@Override
public String getId() {
return id;
}
@Override
public int getSize() {
if (redisClient == null) {
return 0;
}
return Integer.valueOf(redisClient.dbSize().toString());
}
@Override
public void putObject(Object key, Object value) {
if (redisClient != null && key!=null) {
redisClient.set(SerializeUtil.serialize(key.toString()), SerializeUtil.serialize(value));
}
}
@Override
public Object getObject(Object key) {
if (redisClient == null || key==null) {
return null;
}
Object value = SerializeUtil.unserialize(redisClient.get(SerializeUtil.serialize(key.toString())));
System.err.println(getSize());
return value;
}
@Override
public Object removeObject(Object key) {
if (redisClient != null) {
return redisClient.expire(SerializeUtil.serialize(key.toString()), 0);
}
return null;
}
@Override
public void clear() {
if (redisClient != null) {
redisClient.flushDB();
}
}
@Override
public ReadWriteLock getReadWriteLock() {
return readWriteLock;
}
}

 

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
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 在需要加缓存的sqlMap中加入<cache eviction="LRU" type="com.tzz.cache.RedisCache" />
例：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.tzz.web.mapper.article.ArticleMapper">
<resultMap type="com.tzz.cacheableEntity.Article" id="article">
<result property="id" column="ID"/>
<result property="language" column="LANGUAGE" />
<result property="status" column="STATUS" />
<result property="editionPositionId" column="EDITION_POSITION_ID" />
<result property="columnName" column="COLUMN_NAME" />
<result property="editionPositionName" column="EDITION_POSITION_NAME" />
<result property="articleTitle" column="ARTICLE_TITLE" />
<result property="sortNum" column="SORT_NUM" />
<result property="articleContent" column="ARTICLE_CONTENT" jdbcType="CLOB"  javaType = "java.lang.String" />
<result property="remark" column="REMARK" />
<result property="createBy" column="CREATE_BY" />
<result property="createTm" column="CREATE_TM" />
<result property="modifiedTm" column="MODIFIED_TM" />
</resultMap>
<!-- 缓存 -->
<cache
eviction="LRU"
size="100"
readOnly="true"
type="com.tzz.cache.RedisCache"
/>
<!-- 查询 -->
<select id="getListByEpiAndLanguage"  resultMap="article">
select ta.id, ta.language, ta.status, ta.edition_position_id,
ta.article_title, ta.remark, ta.sort_num, ta.article_content, ta.create_by,
to_char(ta.create_tm, 'yyyy-MM-dd') as create_tm,
to_char(ta.modified_tm, 'yyyy-MM-dd') as modified_tm
from TAB_ARTICLE ta
<where>
<if test="editionPositionId != '' and editionPositionId != null">   
and ta.edition_position_id = #{editionPositionId, jdbcType=VARCHAR}
</if>
<if test="language != '' and language != null">   
and ta.language = #{language, jdbcType=VARCHAR}
</if>
</where>
order by ta.sort_num asc
</select>
</mapper>