Spring Boot knowledge notes (scheduled tasks and asynchronous)

First, the regular tasks

1, which increases the injection start classes

@SpringBootApplication    //@SpringBootApplication = @Configuration+@EnableAutoConfiguration+@ComponentScan
@Configuration
@ServletComponentScan   // scan filters servlet, filter annotations 
@MapperScan ( "net.Eleven.demo.Mapper") // scan file corresponding Mapper 

@EnableScheduling    // scheduled tasks scheduled task annotations, scan package which all subclasses of 
@EnableAsync   // enables asynchronous tasks 
public  class XdclassApplication the extends SpringBootServletInitializer {
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(XdclassApplication.class);
    }
    public static void main(String[] args){

        SpringApplication.run(XdclassApplication.class,args);
    }
}

2, the timing of a new task class

package net.Eleven.demo.task;


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

import java.util.Date;

/**
 * Function: regular tasks business class
 *
 */

@Component
public  class TestTask {
 //     @Scheduled (fixedRate = 2000)   // every two seconds to perform a 
    @Scheduled (the cron = "* / * * * * *. 3") // every three seconds to perform a 
    public  void   the sendEmail () {
        System.out.println ( "Current Time:" + new new a Date ());
    }
}

3, the timing of several configuration tasks

3.1, cron timer task expression @Scheduled (cron = "* / 1 * * * * *") denotes per
3.2, fixedRate: How often performed once the timing (after the last execution start time point is performed again xx seconds;)
3.3, fixedDelay: xx seconds after the last execution end point of time to perform again
3.4, fixedDelayString: a string, you can specify a configuration file

Second, asynchronous tasks

1, increase startup class notes (@EnableAsync // enables asynchronous task)

 

2, a new asynchronous task class

package net.Eleven.demo.task;


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

@Component
@Async   // class methods are all asynchronous 
public  class the AsyncTask {
    @Async // methods are marked asynchronous 
    public  void Task1 () throws InterruptedException {
         Long the begin = System.currentTimeMillis ();
        Thread.sleep(1000L);
        long end = System.currentTimeMillis();
        System.out.println ( "time-consuming task 1:" + (END- the begin));
    }

    public void task2() throws InterruptedException{
        long begin = System.currentTimeMillis();
        Thread.sleep(2000L);
        long end = System.currentTimeMillis();
        System.out.println ( "time-consuming task 2:" + (END- the begin));
    }

    public void task3() throws InterruptedException{
        long begin = System.currentTimeMillis();
        Thread.sleep(3000L);
        long end = System.currentTimeMillis();
        System.out.println ( "time-consuming task 3:" + (END- the begin));
    }
}

 

3, the controller which invoked this task

    @Autowired
    private AsyncTask  asyncTask;
    @GetMapping("/api/async")
    public JsonData doTask() throws InterruptedException{
        long begin = System.currentTimeMillis();
        asyncTask.task1();
        asyncTask.task2();
        asyncTask.task3();
        long end = System.currentTimeMillis();
        long totalTime = end-begin;
        System.out.println ( "time-consuming:" + totalTime);
         return JsonData.buildSuccess (totalTime);
    }

 

4, the results