redis 的基本操作

1. 使用jedis 连接redis数据库工具类

<span style="font-size:14px;">package com.umpay.utils;

import java.util.logging.Logger;

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

public class JedisPoolUtil
{
private Logger log = Logger.getLogger(this.getClass().getSimpleName());

private static volatile JedisPool jedisPool = null;

private JedisPoolUtil() {}

public static JedisPool getJedisPoolInstance()
{
if(null == jedisPool)
{
synchronized (JedisPoolUtil.class)
{
if(null == jedisPool)
{
JedisPoolConfig poolConfig = new JedisPoolConfig();
poolConfig.setMaxActive(1000);
poolConfig.setMaxIdle(32);
poolConfig.setMaxWait(100*1000);
poolConfig.setTestOnBorrow(true);

jedisPool = new JedisPool(poolConfig,"192.168.1.37",6379);
}
}
}
return jedisPool;
}

public static void release(JedisPool jedisPool,Jedis jedis)
{
if(null != jedis)
{
jedisPool.returnResourceObject(jedis);
}
}

}
</span>

2. 实现类序列化和反序列化的工具类
<span style="font-size:14px;">package com.umpay.utils;

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) {

}
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;
}

}
</span>
3. 对redis K-V / HashSet的测试

<span style="font-size:14px;">package com.umpay.pojo;

import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import org.junit.Test;

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

import com.umpay.utils.JedisPoolUtil;
import com.umpay.utils.SerializeUtil;

public class TestRedis {

private Jedis jedis = null;

@Test
public void test11() {
// 获取 Jedis连接池实例
JedisPool jedisPool = JedisPoolUtil.getJedisPoolInstance();

// 准备测试数据
User user1 = new User("user01", "nan", "已登录");
User user2 = new User("user02", "nv", "未登录");

try {
// 获取jedis客户端
jedis = jedisPool.getResource();

// 清空redis中所有数据
jedis.flushAll();

// hset 使用在存储对象过程中避免 序列化， 可以使用： key 属性名 value 进行存储
jedis.hset(user1.getUsername(), "username", user1.getUsername());
jedis.hset(user1.getUsername(), "state", user1.getState());

// 根据key获取到所有的 属性名 和 属性值
Map<String, String> user01 = jedis.hgetAll(user1.getUsername());
// 遍历所有的属性名和属性值
Set<Entry<String, String>> entrySet = user01.entrySet();
for (Entry<String, String> entry : entrySet) {
String key = entry.getKey();
String value = entry.getValue();
System.out.println(key + " : " + value);
}

// 如果对应的key的值没有， 则map不是null ， 而是size为0
Map<String, String> user02 = jedis.hgetAll(user2.getUsername());
if (user02 == null || user02.size() == 0) {
System.out.println("user02 is null");
}
// 使用序列化向 redis中存储对象
this.set(user1, user1.getUsername());
this.set(user2, user2.getUsername());
// 取出时需要反序列化
System.out.println(this.get(user1.getUsername()));
System.out.println(this.get(user2.getUsername()));

// 向redis中添加测试数据
jedis.set("key01", "value01");
jedis.set("key02", "value02");
// 设置key02过期时间， 3秒
jedis.expire("key02", 3);

String key02 = jedis.get("key02");
System.out.println("key02 : " + key02);
// 进程阻塞3秒后在吃获取
Thread.sleep(3000);
// 获取到的值为null， 而不是空串
System.out.println("Thread key02 : " + jedis.get("key02"));

// 获取redis中所有key为key开头的键值对
Set<String> keys = jedis.keys("key*");
for (String key : keys) {
System.out.println(key);
}

} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
JedisPoolUtil.release(jedisPool, jedis);
}
}

/** set Object */
public String set(Object object, String key) {
return jedis.set(key.getBytes(), SerializeUtil.serialize(object));
}

/** get Object */
public Object get(String key) {
byte[] value = jedis.get(key.getBytes());
return SerializeUtil.unserialize(value);
}

/** delete a key **/
public boolean del(String key) {
return jedis.del(key.getBytes()) > 0;
}

}
</span>