redis解决同一秒内多次点击造成的超卖问题

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class InventoryService {
    private int inventory = 100; // 商品库存初始数量
    private Lock lock = new ReentrantLock(); // 分布式锁

    public boolean purchaseItem(String itemId) {
        try {
            if (lock.tryLock(1, TimeUnit.SECONDS)) {
                // 检查库存是否充足
                if (inventory > 0) {
                    // 减少库存
                    inventory--;
                    // 执行数据库事务
                    // ...
                    return true;
                }
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
        return false;
    }
}

import redis.clients.jedis.Jedis;
import redis.clients.jedis.Transaction;

public class InventoryService {
    public boolean purchaseItem(String itemId) {
        Jedis jedis = new Jedis("localhost");
        String inventoryKey = "inventory:" + itemId;
        String soldKey = "sold:" + itemId;

        jedis.watch(inventoryKey); // 监视商品库存数量

        int inventory = Integer.parseInt(jedis.get(inventoryKey));
        if (inventory > 0) {
            Transaction transaction = jedis.multi();
            transaction.decr(inventoryKey); // 减少库存数量
            transaction.incr(soldKey); // 增加已售数量
            transaction.exec(); // 提交事务
            return true;
        }

        jedis.unwatch();
        return false;
    }
}