代码
package com.prosay.redis;import java.util.List;import redis.clients.jedis.Jedis;
import redis.clients.jedis.Transaction;public class SaleRunable implements Runnable{
String productKey="iphone8";//监视的key 当前秒杀商品的数量
Jedis jedis = new Jedis("localhost");
String userName;
public SaleRunable(String userName){
this.userName = userName;
} @Override
public void run(){
//商品的key , 秒杀有个数量
//watch 监视一个key,当事务执行之前这个key发生了改变,事务会被打断
jedis.watch(productKey);
String value = jedis.get(productKey);
int num = Integer.valueOf(value);
//这次秒杀的商品是100个iphone8
if(num<=100&&num>=1){
//开启事务
Transaction tx = jedis.multi();
//减少一个商品数量
tx.incrBy(productKey, -1);
//提交事务,如果商品数量发生了改动 则会返回null
List<Object> list = tx.exec();
if(list==null || list.size()==0){
System.out.println(userName+"商品抢购失败!");
}else{
for(Object success : list){
System.out.println(userName+"("+success.toString()+")商品抢购成功,当前抢购成功的人数是:"+(1-(num-100)));
}
}
}else{
System.out.println(userName+"商品已经被抢完了");
}
jedis.close();
}}
测试
package com.prosay.redis;import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;import redis.clients.jedis.Jedis;public class TestMs { public static void main(String[] args) {
Jedis jedis = new Jedis("localhost");
jedis.set("iphone8","100");
jedis.close();
//玩多线程
ExecutorService executor = Executors.newFixedThreadPool(20); for(int i = 0 ; i < 1000; i++){
executor.execute(new SaleRunable("user"+i));
}
executor.shutdown(); }}
转自:https://blog.csdn.net/lzh657083979/article/details/77917088