Java使用延时队列搞定超时订单处理的场景

import lombok.Getter;
import lombok.Setter;
import java.util.Date;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;

@Setter
@Getter
public class ItemDelayed<T> implements Delayed {

    /**默认延迟30分钟*/
    private final static long DELAY = 30 * 60 * 1000L;
    /**数据id*/
    private Long dataId;
    /**开始时间*/
    private long startTime;
    /**到期时间*/
    private long expire;
    /**创建时间*/
    private Date now;
    /**泛型data*/
    private T data;
    
    public ItemDelayed(Long dataId, long startTime, long secondsDelay) {
        super();
        this.dataId = dataId;
        this.startTime = startTime;
        this.expire = startTime + (secondsDelay * 1000);
        this.now = new Date();
    }

    public ItemDelayed(Long dataId, long startTime) {
        super();
        this.dataId = dataId;
        this.startTime = startTime;
        this.expire = startTime + DELAY;
        this.now = new Date();
    }

    @Override
    public int compareTo(Delayed o) {
        return (int) (this.getDelay(TimeUnit.MILLISECONDS) - o.getDelay(TimeUnit.MILLISECONDS));
    }

    @Override
    public long getDelay(TimeUnit unit) {
        return unit.convert(this.expire - System.currentTimeMillis(), TimeUnit.MILLISECONDS);
    }
}

public interface DelayOrder<T> {

    /**
     * 添加延迟对象到延时队列
     *
     * @param itemDelayed 延迟对象
     * @return boolean
     */
    boolean addToOrderDelayQueue(ItemDelayed<T> itemDelayed);

    /**
     * 根据对象添加到指定延时队列
     *
     * @param data 数据对象
     * @return boolean
     */
    boolean addToDelayQueue(T data);

    /**
     * 移除指定的延迟对象从延时队列中
     *
     * @param data
     */
    void removeToOrderDelayQueue(T data);
}

@Slf4j
@Lazy(false)
@Component
public class DelayOwnOrderImpl implements DelayOrder<Order> {

    @Autowired
    private OrderService orderService;

    @Autowired
    private ExecutorService delayOrderExecutor;

    private final static DelayQueue<ItemDelayed<Order>> DELAY_QUEUE = new DelayQueue<>();

    /**
     * 初始化时加载数据库中需处理超时的订单
     * 系统启动:扫描数据库中未支付(要在更新时:加上已支付就不用更新了),未过期的的订单
     */
    @PostConstruct
    public void init() {
        log.info("系统启动:扫描数据库中未支付,未过期的的订单");
        List<Order> orderList = orderService.selectFutureOverTimeOrder();
        for (Order order : orderList) {
            ItemDelayed<Order> orderDelayed = new ItemDelayed<>(order.getId(), order.getCreateDate().getTime());
            this.addToOrderDelayQueue(orderDelayed);
        }
        log.info("系统启动:扫描数据库中未支付的订单,总共扫描了" + orderList.size() + "个订单,推入检查队列,准备到期检查...");

        /*启动一个线程，去取延迟订单*/
        delayOrderExecutor.execute(() -> {
            log.info("启动处理的订单线程:" + Thread.currentThread().getName());
            ItemDelayed<Order> orderDelayed;
            while (true) {
                try {
                    orderDelayed = DELAY_QUEUE.take();
                    //处理超时订单
                    orderService.updateCloseOverTimeOrder(orderDelayed.getDataId());
                } catch (Exception e) {
                    log.error("执行自营超时订单的_延迟队列_异常:" + e);
                }
            }
        });
    }

    /**
     * 加入延迟消息队列
     **/
    @Override
    public boolean addToOrderDelayQueue(ItemDelayed<Order> orderDelayed) {
        return DELAY_QUEUE.add(orderDelayed);
    }

    /**
     * 加入延迟消息队列
     **/
    @Override
    public boolean addToDelayQueue(Order order) {
        ItemDelayed<Order> orderDelayed = new ItemDelayed<>(order.getId(), order.getCreateDate().getTime());
        return DELAY_QUEUE.add(orderDelayed);
    }

    /**
     * 从延迟队列中移除 主动取消就主动从队列中取出
     **/
    @Override
    public void removeToOrderDelayQueue(Order order) {
        if (order == null) {
            return;
        }
        for (Iterator<ItemDelayed<Order>> iterator = DELAY_QUEUE.iterator(); iterator.hasNext(); ) {
            ItemDelayed<Order> queue = iterator.next();
            if (queue.getDataId().equals(order.getId())) {
                DELAY_QUEUE.remove(queue);
            }
        }
    }
}