基于redis内存数据库简单使用
在ecplise中使用内存数据的客端户,前提要准备要下载两个jar包 commons-pool2-2.0.jar jedis-2.4.2.jar 前提准备做好了,那我们就开启redis的服务,打开一个命令窗口输入如下命令:redis-server 或redis-server redis根目\redis.conf 服务器已经开启了,注意
在ecplise中使用内存数据的客端户,前提要准备要下载两个jar包
commons-pool2-2.0.jar
jedis-2.4.2.jar
前提准备做好了,那我们就开启redis的服务,打开一个命令窗口输入如下命令:redis-server 或redis-server redis根目\redis.conf
服务器已经开启了,注意端号是6377
2.在eclipse 创建一个项目,把redist需要的包导入项目中
3.写一个Jedis工具类
public class JedisUtil {
private static String HOST="127.0.0.1"; //本机地址
private static Integer PORT=6379; //服务端口
private static JedisPoolConfig config; //连接池的配置对象
private static JedisPool pool; //连接池对象
static{
config = new JedisPoolConfig();
config.setMaxIdle(1024*10); //设置内存大小
pool = new JedisPool(config,HOST);
}
/**
*
* @return 从连接池里获取一个Jedis对象
*/
public static Jedis getPoolJedis(){
return pool.getResource();
}
/**
* 手动把Jedis对象,回放到连接池里
*/
public static void returnPoolJedis(Jedis jedis){
pool.returnResource(jedis);
}
/**
* @return 直接创建一个Jedis连接
*/
public static Jedis getJedis(){
return new Jedis(HOST, PORT);
}
}
4.写一个客户端类操作jedis
public class Client {
public static void main(String[] args) {
//simpleSet();
mSet();
}
private static void mSet() {
//注意 如果使用 JedisUtil.getJedis(); 是直接创建一个jredis对象,所以不受连接池管理,所以不能回放到连接池里
Jedis jedis = JedisUtil.getPoolJedis();
//设置值多个值
jedis.mset("userName","user1","pwd","123");
//取值
List
for (String string : list) {
System.out.println(string);
}
jedis.flushDB();
JedisUtil.returnPoolJedis(jedis);
}
private static void simpleSet() {
Jedis jedis = JedisUtil.getPoolJedis();
//设置值
jedis.set("userName", "user1");
//取值
System.out.println("userName:"+jedis.get("userName"));
//清空内存数据库
jedis.flushDB();
JedisUtil.returnPoolJedis(jedis);
}
}
现在可以在redist客户端对数据进行取值
打开一个命令窗口,输入命令 redis-cli 开启客户端,原后进行赋值

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