1.继承Delayed类

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package com.jcxx.common.util.delayed;

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

/**
 * 延时队列
 *
 * @param <T>
 */
public class DelayedItem<T> implements Delayed {

    /**
     * 到期时间
     */
    private final long activeTime;
    /**
     * 数据
     */
    private final T data;

    public DelayedItem(long activeTime, T data, TimeUnit timeUnit) {
        // 将传入的时间转换为超时的时刻
        this.activeTime = System.currentTimeMillis() + (activeTime > 0 ? timeUnit.toMillis(activeTime) : 0);
        this.data = data;
    }

    public long getActiveTime() {
        return activeTime;
    }

    public T getData() {
        return data;
    }

    /**
     * 按照剩余时间进行排序
     *
     * @param delayed
     * @return
     */
    @Override
    public int compareTo(Delayed delayed) {
        DelayedItem delayedItem = (DelayedItem) delayed;

        // 剩余时间-当前传入的时间= 实际剩余时
        long diff = this.activeTime - delayedItem.getActiveTime();
        // 排序
        if (diff <= 0) {
            return -1;
        } else {
            return 1;
        }
    }

    /**
     * 获取剩余时间
	 * <p>
     * 延迟任务是否到时就是按照这个方法判断如果返回的是负数则说明到期否则还没到期
     *	
     * @param unit
     * @return
     */
    @Override
    public long getDelay(TimeUnit unit) {
        return activeTime - System.currentTimeMillis();
    }
}

2.使用方式

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public static void main(String[] args) throws InterruptedException {
    DelayQueue<DelayedItem<Void>> queue = new DelayQueue<>();
    queue.offer(new DelayedItem<>(1, null, TimeUnit.MINUTES));
    DelayedItem<Void> item = queue.take();
    System.out.format("name:{%s}, time:{%s}\n", item.getData(), LocalDateTime.now().format(DateTimeFormatter.ISO_DATE_TIME));
    
}