SpringBoot- Three tasks

Asynchronous tasks

1. Build

Create an asynchronous processing class AsynService

package com.gip.service;

import org.springframework.stereotype.Service;

@Service
public class AsynService {

    public void hello(a)  {
        try {
            Thread.sleep(3000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        System.out.println("Data is being processed."); }}Copy the code

Use the thread.sleep (3000); Simulation process

And then we call this class real column method hello() in the Controller

AsynController

package com.gip.Controller;

import com.gip.service.AsynService;
import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class AsynController {
    @Autowired
    AsynService asynService;

    @GetMapping("/hello")
    public String hell0(a) {
        asynService.hello();
        return "hello"; }}Copy the code

Start the project and see what happens

The browser waits 3 seconds for a response

Before returning the Hello string

2. Enable asynchronous annotations

Add @async to the hello method door of the asynchronous class

Then in the asynchronous support SpringbootTestApplication main start up on the class

What functions should be enabled? @enable+…. function

Restart the project to run, discover and do not stall, and asynchronous processing is complete

The mail task

1. Add dependencies

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-mail</artifactId>
</dependency>
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Double-click Shift to find the source code for the mail configuration

It’s pretty clear here

You can configure the following properties

2. Start the configuration

First go to your email to enable this feature

Then configure it in application.properties

3. The test

Write a simple message in the test class

package com.gip;

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSenderImpl;
import org.springframework.scheduling.annotation.Async;

@SpringBootTest
class SpringbootTestApplicationTests {

    @Autowired
    JavaMailSenderImpl mailSender;
    @Test
    void contextLoads(a) {
        SimpleMailMessage simpleMailMessage=new SimpleMailMessage();
        simpleMailMessage.setSubject("This is my test send email.");
        simpleMailMessage.setText("Here's the text.");
        simpleMailMessage.setFrom("[email protected]");
        simpleMailMessage.setTo("[email protected]"); mailSender.send(simpleMailMessage); }}Copy the code

First inject an instance of the implementation class

Then define the simple message

SimpleMailMessage simpleMailMessage=new SimpleMailMessage();
simpleMailMessage.setSubject("This is my test send email.");
simpleMailMessage.setText("Here's the text.");
// From where, the sender
simpleMailMessage.setFrom("[email protected]");
// To whom, the receiver
simpleMailMessage.setTo("[email protected]");
mailSender.send(simpleMailMessage);
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Send with the mailsender. send method

The test results are as follows:

Create a new complex message

@Test
void contextLoads2(a) throws MessagingException {
    // Create a complex message
    MimeMessage mimeMessage = mailSender.createMimeMessage();
    MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true);
    helper.setSubject("This is my test send email 222");
    helper.setText(
 .true);
    helper.setFrom("[email protected]");
    helper.setTo("[email protected]");

    / / accessories
   helper.addAttachment("01.jpg".new File("F:\\ desktop wallpaper \\01.jpg"));


    mailSender.send(mimeMessage);
}
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Note: idea method shortcut key: Ctrl+P ‘parameter prompt

Timing task

Add the @enablesCheduling annotation to the startup class

Create ScheduledService class

package com.gip.service;

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

@Service
public class ScheduledService {
// A Cron expression is a string separated by five or six Spaces
// second (0~59)
// min (0~59)
// hour (0~23)
// Day (day and month) (0 to 31, but you need to consider the number of days in your month)
// month (0~11)
// day (week) (1~7 1=SUN or SUN, MON, TUE, WED, THU, FRI, SAT)
// Year (1970-2099)
    @Scheduled(cron = "* * * * * ?" )
    public void hello(a){
        System.out.println("Scheduled task enabled"); }}Copy the code

Note: Spring Task does not support up to years, so you can only cron expressions up to 6 bits

? It can only be used for dates and days. You can also use * instead

Timer function is not powerful, and after running error, the life cycle ends, can not be executed in the future. So you don’t use Java Timer, you use Quartz