【Spring】IoC容器 控制反转 与 DI依赖注入 XML实现版本 第二期

实现思路

引入Jedis

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>3.7.0</version>
</dependency>

指令简介

zadd

zrem

zrangeByScore

Java实现Redis延时队列

import redis.clients.jedis.Jedis;
import java.util.Set;

public class DelayQueueWithRedis {

    private Jedis jedis;
    private String queueKey;

    public DelayQueueWithRedis(Jedis jedis, String queueKey) {
        this.jedis = jedis;
        this.queueKey = queueKey;
    }

    // 添加消息到延迟队列
    public void push(String message, long delaySeconds) {
        // 计算消息的分数，这里使用消息进入队列的时间加上延迟时间
        long score = System.currentTimeMillis() / 1000 + delaySeconds;
        //向有序集合添加一个成员，并设置其分数
        jedis.zadd(queueKey, score, message);
    }

    // 获取并消费一条消息
    public String pop() {
        while (true) {
            long now = System.currentTimeMillis() / 1000;
            // 只获取分数在0到当前时间的元素
            Set<String> messages = jedis.zrangeByScore(queueKey, 0, now, 0, 1);
            if (messages.isEmpty()) {
                System.out.println("No messages");
                // 没有可消费的消息，休眠一会儿继续尝试
                try {
                    Thread.sleep(500);
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                    break;
                }
            } else {
                String message = messages.iterator().next();
                // 从有序集合中移除一个成员
                jedis.zrem(queueKey, message);
                return message;
            }
        }
        return null;
    }
}

import redis.clients.jedis.Jedis;

/**
 * @Author: zhangximing
 * @Email: 530659058@qq.com
 * @Date: 2024/2/19 16:53
 * @Description: 生产者端测试
 */
public class MainP {

    public static void main(String[] args) {
        Jedis jedis = new Jedis("localhost",6379);
        DelayQueueWithRedis delayQueue = new DelayQueueWithRedis(jedis, "delay_queue");

        // 添加延时消息
        delayQueue.push("message1", 5);
        delayQueue.push("message2", 10);
        delayQueue.push("message3", 8);
    }

}

import redis.clients.jedis.Jedis;

/**
 * @Author: zhangximing
 * @Email: 530659058@qq.com
 * @Date: 2024/2/19 16:51
 * @Description: 消费者端测试
 */
public class MainC {

    public static void main(String[] args) {
        Jedis jedis = new Jedis("localhost",6379);
        DelayQueueWithRedis delayQueue = new DelayQueueWithRedis(jedis, "delay_queue");

        // 消费延时消息
        while (true) {
            String message = delayQueue.pop();
            if (message != null) {
                System.out.println("Consumed: " + message);
            }
        }
    }
}