基于Redisson的延迟队列实现

package com.dong.mytest.demo.client;

import cn.hutool.extra.spring.SpringUtil;
import com.dong.mytest.demo.common.dto.DelayMessage;
import com.dong.mytest.demo.common.util.DateUtil;
import com.dong.mytest.demo.service.delayqueue.DelayQueueConsumer;
import com.google.common.collect.Lists;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RBlockingQueue;
import org.redisson.api.RDelayedQueue;
import org.redisson.api.RedissonClient;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

/**
 * @author dong
 */
@Slf4j
@Component
public class RedissonDelayQueueClient implements InitializingBean {

    @Resource
    private RedissonClient redissonClient;

    private final Map<String, RDelayedQueue<DelayMessage>> delayQueueMap = new ConcurrentHashMap<>(16);

    public void addDelayMessage(DelayMessage delayMessage) {
        log.info("delayMessage={}", delayMessage);
        if (delayQueueMap.get(delayMessage.getQueueName()) == null) {
            log.warn("queueName={},该延迟队列不存在，请确认后再试...", delayMessage.getQueueName());
            return;
        }
        delayMessage.setCreateTime(DateUtil.getNowFormatStr());
        RDelayedQueue<DelayMessage> rDelayedQueue = delayQueueMap.get(delayMessage.getQueueName());
        rDelayedQueue.offer(delayMessage, delayMessage.getDelayTime(), delayMessage.getTimeUnit() == null ? TimeUnit.SECONDS : delayMessage.getTimeUnit());
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        // 有新的延迟队列在这里添加，队列消费类需要继承DelayQueueConsumer，并且service名称为 ${queueName}Consumer
        List<String> queueNameList = Lists.newArrayList("orderAutoCancelDelayQueue");

        // 加载延迟队列
        for (String queueName : queueNameList) {
            DelayQueueConsumer delayQueueConsumer = SpringUtil.getBean(queueName + "Consumer");
            if (delayQueueConsumer == null) {
                throw new RuntimeException("queueName=" + queueName + ",delayQueueConsumer=null,请检查配置...");
            }
            // Redisson的延时队列是对另一个队列的再包装，使用时要先将延时消息添加到延时队列中，当延时队列中的消息达到设定的延时时间后，
            // 该延时消息才会进行进入到被包装队列中，因此，我们只需要对被包装队列进行监听即可。
            RBlockingQueue<DelayMessage> rBlockingQueue = redissonClient.getBlockingDeque(queueName);
            RDelayedQueue<DelayMessage> rDelayedQueue = redissonClient.getDelayedQueue(rBlockingQueue);
            delayQueueMap.put(queueName, rDelayedQueue);

            // 订阅新元素的到来，调用的是takeAsync()，异步执行
            rBlockingQueue.subscribeOnElements(delayQueueConsumer::execute);
        }
    }
}

package com.dong.mytest.demo.service.delayqueue;

import com.dong.mytest.demo.common.dto.DelayMessage;

/**
 * @author dong
 */
public interface DelayQueueConsumer {

    /**
     * 执行延迟消息
     *
     * @param delayMessage delayMessage
     */
    void execute(DelayMessage delayMessage);

}

package com.dong.mytest.demo.service.delayqueue.impl;

import com.dong.mytest.demo.common.dto.DelayMessage;
import com.dong.mytest.demo.service.delayqueue.DelayQueueConsumer;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;

/**
 * @author dong
 */
@Service("orderAutoCancelDelayQueueConsumer")
@Slf4j
public class OrderAutoCancelDelayQueueConsumer implements DelayQueueConsumer {

    @Override
    public void execute(DelayMessage delayMessage) {
        log.info("====OrderAutoCancelConsumer=====delayMessage={}", delayMessage);
    }
}

package com.dong.mytest.demo.common.dto;

import com.alibaba.fastjson.JSON;
import lombok.Data;

import java.io.Serializable;
import java.util.concurrent.TimeUnit;

/**
 * @author dong
 */
@Data
public class DelayMessage implements Serializable {

    private String queueName;

    private Long delayTime;

    private TimeUnit timeUnit;

    private String msgBody;

    private String createTime;

    @Override
    public String toString() {
        return JSON.toJSONString(this);
    }
}