您好,登录后才能下订单哦!
密码登录
登录注册
点击 登录注册 即表示同意《亿速云用户服务条款》
小编给大家分享一下如何实现Java中的延迟队列,希望大家阅读完这篇文章之后都有所收获,下面让我们一起去探讨吧!
常见的实现方法主要有:定时任务扫描、RocketMQ延迟队列、Java自动的延迟队列、监听Redis Key过期等等
首先,定义一个延迟任务
package com.cjs.example;
import lombok.Data;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;
/**
* @author ChengJianSheng
* @since 2021/3/18
*/
@Data
public class DelayTask implements Delayed {
private Long orderId;
private long expireTime;
public DelayTask(Long orderId, long expireTime) {
this.orderId = orderId;
this.expireTime = expireTime;
}
@Override
public long getDelay(TimeUnit unit) {
return expireTime - System.currentTimeMillis();
}
@Override
public int compareTo(Delayed o) {
return (int) (getDelay(TimeUnit.MILLISECONDS) - o.getDelay(TimeUnit.MILLISECONDS));
}
}
然后,定义一个管理类
package com.cjs.example;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;
import java.util.concurrent.DelayQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
/**
* @author ChengJianSheng
* @since 2021/3/19
*/
@Slf4j
@Component
public class DelayQueueManager implements CommandLineRunner {
private DelayQueue<DelayTask> queue = new DelayQueue<>();
@Autowired
private ParkOrderQueryHandler handler;
@Override
public void run(String... strings) throws Exception {
ExecutorService executorService = Executors.newSingleThreadExecutor();
executorService.execute(new Runnable() {
@Override
public void run() {
while (true) {
try {
DelayTask task = queue.take();
handler.handle(task);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
}
public void put(DelayTask task) {
queue.put(task);
}
}
插入任务
@Slf4j
@Service
public class PayServiceImpl implements PayService {
@Autowired
private DelayQueueManager delayQueueManager;
@Override
public void pay() {
delayQueueManager.put(new DelayTask(1, 15));
delayQueueManager.put(new DelayTask(2, 30));
delayQueueManager.put(new DelayTask(3, 60));
}
}
修改redis.conf文件
# bind 127.0.0.1 -::1
protected-mode no
notify-keyspace-events Ex
[root@localhost redis-6.2.1]$ src/redis-server redis.conf
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.4.4</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo0401</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo0401</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
RedisConfig.java
package com.example.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.listener.RedisMessageListenerContainer;
/**
* @author ChengJianSheng
* @since 2021/4/2
*/
@Configuration
public class RedisConfig {
@Bean
public RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory) {
RedisMessageListenerContainer container = new RedisMessageListenerContainer();
container.setConnectionFactory(connectionFactory);
return container;
}
}
创建一个监听类
package com.example.listener;
import org.springframework.data.redis.connection.Message;
import org.springframework.data.redis.listener.KeyExpirationEventMessageListener;
import org.springframework.data.redis.listener.RedisMessageListenerContainer;
import org.springframework.stereotype.Component;
/**
* @author ChengJianSheng
* @since 2021/4/2
*/
@Component
public class MyRedisKeyExpirationListener extends KeyExpirationEventMessageListener {
public MyRedisKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {
super(listenerContainer);
}
@Override
public void onMessage(Message message, byte[] pattern) {
String expiredKey = message.toString();
System.out.println("监听到Key: " + expiredKey + " 已过期");
}
}
看完了这篇文章,相信你对“如何实现Java中的延迟队列”有了一定的了解,如果想了解更多相关知识,欢迎关注亿速云行业资讯频道,感谢各位的阅读!
免责声明:本站发布的内容(图片、视频和文字)以原创、转载和分享为主,文章观点不代表本网站立场,如果涉及侵权请联系站长邮箱:is@yisu.com进行举报,并提供相关证据,一经查实,将立刻删除涉嫌侵权内容。