需要先搭好SSM开发环境，并安装好Redis，下面是具体的实现步骤：
1、在项目中引入jedis架包：jedis-2.8.2.jar、spring-data-redis-1.6.2.RELEASE.jar和commons-pool-1.6.jar，注意引入的jar版本，过高或过低都有可能引发异常，上面提到这些版本组合亲测可用；
2、编写Redis需要用的2个工具类 RedisUtil.java和SerializeUtil.java
3、新增一个Cache类MybatisRedisCache，实现 org.apache.ibatis.cache.Cache 接口
4、开启mybatis对缓存的支持，在本项目中，是修改 mybatis-config.xml文件
5、在相关的 mapper.xml 添加自定义的缓存类MybatisRedisCache
RedisUtil工具类是用以跟Redis数据通信，SerializeUtil为序列化工具类，也是lang包下的工具，主要用于序列化操作，同时提供对象克隆接口。下面是具体代码：
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
public class RedisUtil {
private static String ADDR = "127.0.0.1";
private static int PORT = 6379;
private static int MAX_ACTIVE = 1024;
private static int MAX_IDLE = 200;
private static int MAX_WAIT = 100000;
private static int TIMEOUT = 10000;
private static boolean TEST_ON_BORROW = true;
private static JedisPool jedisPool = null;
static {
try{
JedisPoolConfig config = new JedisPoolConfig();
config.setMaxIdle(MAX_IDLE);
config.setMaxWaitMillis(MAX_WAIT);
config.setTestOnBorrow(TEST_ON_BORROW);
jedisPool = new JedisPool(config,ADDR,PORT,TIMEOUT);
}catch (Exception e) {
e.printStackTrace();
}
}
public synchronized static Jedis getJedis(){
try{
if(jedisPool != null){
Jedis jedis = jedisPool.getResource();
return jedis;
}else{
return null;
}
}catch (Exception e) {
e.printStackTrace();
return null;
}
}
public static void returnResource(final Jedis jedis){
if(jedis != null){
jedisPool.returnResource(jedis);
}
}
}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) {
if (bytes == null)
return null;
ByteArrayInputStream bais = null;
try {
// 反序列化
bais = new ByteArrayInputStream(bytes);
ObjectInputStream ois = new ObjectInputStream(bais);
return ois.readObject();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
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;
public class MybatisRedisCache implements Cache {
private static Logger logger = LoggerFactory.getLogger(MybatisRedisCache.class);
/** 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;
}
public String getId() {
return this.id;
}
public void putObject(Object key, Object value) {
logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>putObject:"+key+"="+value);
RedisUtil.getJedis().set(SerializeUtil.serialize(key.toString()), SerializeUtil.serialize(value));
}
public Object getObject(Object key) {
Object value = SerializeUtil.unserialize(RedisUtil.getJedis().get(SerializeUtil.serialize(key.toString())));
logger.debug(">>>>>>>>>>>>>>>>>>>>>>>>getObject:"+key+"="+value);
return value;
}
public Object removeObject(Object key) {
return RedisUtil.getJedis().expire(SerializeUtil.serialize(key.toString()),0);
}
public void clear() {
RedisUtil.getJedis().flushDB();
}
public int getSize() {
return Integer.valueOf(RedisUtil.getJedis().dbSize().toString());
}
public ReadWriteLock getReadWriteLock() {
return readWriteLock;
}
}mybatis-config.xml文件，在spring-mybatis.xml文件中选择全局加载：
以下是mybatis-config.xml详细代码：
最后在需要缓存的映射文件mapper.xml的namespace加上引用的
结果运行的时候报了这个异常： jedis.exceptions.JedisDataException: ERR Client sent AUTH, but no password is set
意思就是redis服务器没有设置密码，但客户端向其发送了AUTH请求。 此外，要缓存的类需要implements Serializable。 如果怀疑你安装的Redis有问题，可通过下面的方法进行测试：
@Test public void testRedis(){ //连接本地的 Redis 服务 Jedis jedis = new Jedis("localhost"); System.out.println("连接成功"); //查看服务是否运行 System.out.println("服务正在运行: "+jedis.ping()); //设置 redis 字符串数据 jedis.set("success", "oobom"); // 获取存储的数据并输出 System.out.println("redis 存储的字符串为: "+ jedis.get("success")); }更多redis知识请关注redis数据库教程栏目。
