本地延迟队列

本地延迟队列

DelayQueue是无界的

特殊注意: 放入DelayQueue队列中的数据必须实现Delay接口,可以通过指定方法获取到是否到执行时间及比较运算逻辑

1.定义本地延迟队列

@Slf4j
@Component
public class NotificationHisRetryQueue {

    private DelayQueue<NotificationResult> queue;
    @PostConstruct
    public void init() {
        queue = new DelayQueue<>();
    }

    public void push(NotificationResult data) {
        queue.offer(data);
    }

    public BlockingQueue<NotificationResult> getQueue() {
        return queue;
    }
}

2.NotificationResult实现接口Delayed

@AllArgsConstructor
@NoArgsConstructor
@Data
@Builder
class NotificationResult implements Delayed{
	Long runAt;

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

    @Override
    public int compareTo(Delayed o) {
        NotificationResult object  = (NotificationResult) o;
        return this.runAt.compareTo(object.runAt);
    }

}

3. 队列里生产数据

// 按照默认延迟30s的数据进行生产
// 只有30s到期的数据才会被取出
public void pushLocalRetryQueue(NotificationResult notificationResult){
        log.info("通知历史{}入mq失败,进入本地重试队列,延迟30秒后进行重试",notificationResult);
        notificationResult.setRunAt(System.currentTimeMillis() + 1000 * 30);
        notificationHisRetryQueue.push(notificationResult);
    }

4.队列消费数据

NotificationResult result = notificationHisRetryQueue.getQueue().take();