利用 Redis 队列操作的原子性实现秒杀

1. 添加一个队列模拟商品列表

lpush productlist 1 2 3 4 5 6 7 8 9 10

1. 利用多线程模拟 30 个人抢购这 10 件商品：

package demo;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

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

/**
 * @author qujianlei
 * @date 2019年1月5日 下午2:49:11
 * @description 通过Redis队列的原子操作实现秒杀
 */
public class RedisSpike {

    public static void main(String[] args) {
        // redis的队列操作是原子操作
        // eg: 30个人抢10个商品
        // lpush productlist 1 2 3 4 5 6 7 8 9 10 商品ID号
        JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
        jedisPoolConfig.setMaxIdle(10);
        jedisPoolConfig.setMaxWaitMillis(10000);
        jedisPoolConfig.setMaxTotal(1024);
        
        JedisPool jedisPool = new JedisPool(jedisPoolConfig, "127.0.0.1", 6379);
        
        ExecutorService executor = Executors.newFixedThreadPool(30);
        
        for (int i = 0; i < 30; i++) {
            executor.execute(new SpikeTask(i, jedisPool));
        }
        
        executor.shutdown();
    }

}

class SpikeTask implements Runnable {

    private int customerId;
    
    private JedisPool jedisPool;
    
    public SpikeTask (int customerId, JedisPool jedisPool) {
        this.customerId = customerId;
        this.jedisPool = jedisPool;
    }
    
    @Override
    public void run() {
        
        // 执行秒杀
        Jedis client = jedisPool.getResource();
        
        String productId = client.lpop("productlist");
        
        if (productId != null && productId.length() != 0) {
            System.out.println("顾客" + customerId + "抢到了" + productId + "号商品");
        } else {
            System.out.println("顾客" + customerId + "没有抢到商品");
        }
        
    }
}

2. 秒杀结果：