7.4 异步、定时和邮件发送任务

一.任务分类

  • 异步任务

  • 定时任务

  • 邮件发送任务

二.异步任务

1.主要两个步骤

  • 在异步方法上加上注解@Async

  • 在springBoot的启动类中开启注解@EnableAsync

2.编写异步程序

  • 编写一个Service层的异步方法并使用@Async

  • 在控制层调用异步方法

  • 在springBoot启动类中开启注解@EnableAsync

(1)编写一个Service层的异步方法并使用@Async

import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;

@Service
public class AsyncService {

    //告诉Spring这是一个异步方法
    @Async
    public void hello(){

        try {
            Thread.sleep(3000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        System.out.println("数据正在处理...");
    }
}

(2)在控制层调用异步方法

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import ustc.wzh.service.AsyncService;

@RestController
public class AsyncController {

    @Autowired
    AsyncService asyncService;

    @RequestMapping("/hello")
    public String hello(){
        asyncService.hello(); //如果不设置为异步任务则会停止三秒卡住页面
        return "OK";
    }
}

(3)在springBoot启动类中开启注解@EnableAsync

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableAsync;

//开启异步注解功能
@EnableAsync
@SpringBootApplication
public class Springboot09TaskApplication {

    public static void main(String[] args) {
        SpringApplication.run(Springboot09TaskApplication.class, args);
    }

}

三.邮件发送任务

1.步骤

  • 导入依赖

  • 查看自己的邮箱打开POP3和SMTP服务以及拿到授权码

  • 编写邮件发送类

  • 测试

2.导入依赖

<!--邮件发送-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-mail</artifactId>
</dependency>

3.查看自己的邮箱打开POP3和SMTP服务以及拿到授权码

4.编写邮件发送类

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSenderImpl;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.io.File;
import java.io.IOException;

@Component
public class SendMailTask {


    private static JavaMailSenderImpl mailSender;

    @Autowired
    private JavaMailSenderImpl javaMailSender;

    @PostConstruct
    public void init(){
        mailSender = javaMailSender;
    }

    //简单邮件发送(只有文字内容)
    public static void testSendMailTask1(){

        SimpleMailMessage mailMessage = new SimpleMailMessage();

        mailMessage.setSubject("这是邮件的主题");
        mailMessage.setText("这是邮件的内容");

        mailMessage.setTo("18855162320@163.com");
        mailMessage.setFrom("464407764@qq.com");

        mailSender.send(mailMessage);
    }

    //复杂邮件的发送
    public static void testSendMailTask2() throws MessagingException, IOException {

        MimeMessage mimeMessage = mailSender.createMimeMessage();

        // 组装
        MimeMessageHelper helper = new MimeMessageHelper(mimeMessage,true,"utf-8");

        // 发送的标题和文字内容(可以使用html标签需要true)
        helper.setSubject("这是邮件的主题");
        helper.setText("<p style='color:red'>这是邮件的内容</p>",true);


        // 附件
        helper.addAttachment("图片1.png", new File("C:\\Users\\DELL\\Desktop\\1.png"));
        helper.addAttachment("图片2.png", new File("C:\\Users\\DELL\\Desktop\\2.png"));

        helper.setTo("18855162320@163.com");
        helper.setFrom("464407764@qq.com");


        mailSender.send(mimeMessage);
    }

}

5.测试发送成功

四.定时任务

  • TaskScheduler:任务调度者
  • TaskExecutor:任务执行者
  • @EnableScheduling:开启定时功能注解
  • @Scheduled:设置定时的时间执行
  • cron表达式

1.编写每两秒自动执行业务

import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;

@Service
public class ScheduleService {


    //corn表达式:秒 分 时 日 月 周几(0~7从周日到周日) 年(一般省略)
    @Scheduled(cron = "0/2 * * * * ?")
    public void hello(){
        System.out.println("hello,被执行了!");
    }
}

2.配置Springboot启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;

@EnableAsync //开启异步注解功能
@EnableScheduling //开启定时功能注解
@SpringBootApplication
public class Springboot09TaskApplication {

    public static void main(String[] args) {
        SpringApplication.run(Springboot09TaskApplication.class, args);
    }

}

3.启动springboot后自动执行定时任务

  • 测试成功

 

posted @ 2020-03-07 02:41  All_just_for_fun  阅读(213)  评论(0编辑  收藏  举报