@Scheduled 注解的使用

package com.example.demo;

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

@SpringBootApplication
@EnableScheduling
public class DemoApplication {

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

package com.example.demo;

import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.Scheduled;

import java.util.Date;

/**
 * Created by yawn on 2017-07-13.
 */

@Configuration
public class TaskTest {

    TaskTest(){
        System.out.println("construct =======>>>>>>>>>>>");
    }

    // fixedDelay 和 fixedDelayString 马上开始执行任务
    @Scheduled(fixedDelay = 1000)
    public void task() {
        System.out.println("1>>>>>>>>===========");
    }
    @Scheduled(fixedDelayString = "2000")
    public void task4() {
        System.out.println("4===========>>>>>>>>");
    }




    // 延迟后执行任务
    @Scheduled(initialDelay = 5000, fixedRate = 1000)
    public void task1() {
        System.out.println("2===========>>>>>>>>");
    }

    @Scheduled(initialDelayString = "5000", fixedRateString = "1000")
    public void task3() {
        System.out.println("3===========>>>>>>>>");
    }


    /**
     * cron: A cron-like expression, extending the usual UN*X definition to include
     * triggers on the second as well as minute, hour, day of month, month
     * and day of week.  e.g. {@code "0 * * * * MON-FRI"} means once per minute on
     * weekdays (at the top of the minute - the 0th second).
     *
     * 这里表达式只有六位，写成七位就会报错
     * 此六位分别表示      秒、分钟、小时、日、月、星期（没有年）
     */
    @Scheduled(cron = "3,13,23,33 * * * * ?")
    public void task2() {
        System.out.println(new Date(System.currentTimeMillis()));
    }
}