TestDelayQueue.java

package com.cjs.block_queue;

import java.util.concurrent.DelayQueue;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;

public class TestDelayQueue {

    public static void main(String[] args) throws InterruptedException {
        DelayQueue<MovieTiket> delayQueue = new DelayQueue<>();
        MovieTiket ticket = new MovieTiket("电影票0", 10000);
        delayQueue.put(ticket);
        MovieTiket ticket2 = new MovieTiket("电影票1", 5000);
        delayQueue.put(ticket2);
        MovieTiket tiket3 = new MovieTiket("电影票2", 8000);
        delayQueue.put(tiket3);
        System.out.println("message:--->入队完毕");

        while (delayQueue.size() > 0) {
            try {
                ticket = delayQueue.take();
                System.out.println("电影票出队:" + ticket.getMsg() + ":::" + ticket);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

    }
}

class MovieTiket implements Delayed {
    //延迟时间
    private final long delay;
    //到期时间
    private final long expire;
    //数据
    private final String msg;
    //创建时间
    private final long now;

    public long getDelay() {
        return delay;
    }

    public long getExpire() {
        return expire;
    }

    public String getMsg() {
        return msg;
    }

    public long getNow() {
        return now;
    }

    /**
     * @param msg   消息
     * @param delay 延期时间
     */
    public MovieTiket(String msg, long delay) {
        this.delay = delay;
        this.msg = msg;
        now = System.currentTimeMillis();
        expire = now + delay;    //到期时间 = 当前时间+延迟时间
    }

    /**
     * @param msg
     */
    public MovieTiket(String msg) {
        this(msg, 1000);
    }

    public MovieTiket() {
        this(null, 1000);
    }

    /**
     * 获得延迟时间   用过期时间-当前时间,时间单位毫秒
     *
     * @param unit
     * @return
     */
    public long getDelay(TimeUnit unit) {
        return unit.convert(this.expire
            - System.currentTimeMillis(), TimeUnit.MILLISECONDS);
    }

    /**
     * 用于延迟队列内部比较排序  当前时间的延迟时间 - 比较对象的延迟时间
     * 越早过期的时间在队列中越靠前
     *
     * @param delayed
     * @return
     */
    public int compareTo(Delayed delayed) {
        return (int) (this.getDelay(TimeUnit.MILLISECONDS)
            - delayed.getDelay(TimeUnit.MILLISECONDS));
    }

    @Override
    public String toString() {
        return "MovieTiket{" +
            "delay=" + delay +
            ", expireAt=" + expire +
            ", msg='" + msg + '\'' +
            ", now=" + now +
            ", 已经过去=" + (expire - now) +
            '}';
    }
}