方式一：基于注解@Scheduled實(shí)現(xiàn)簡單定時(shí)器

image.png

DemoApplication文件

package com.example.schedule.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(value = "com.example.schedule.schedule")
public class DemoApplication {

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

}

MySchedule文件

package com.example.schedule.schedule;

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

@EnableScheduling
@Configuration
public class MySchedule {

    @Scheduled(fixedRate = 3000)
    private void configureTasks1() {
        System.out.printf("xxxx");
    }

    @Scheduled(fixedRate = 6000)
    private void configureTasks2() {
        System.out.printf("xxxx");
    }
}

注解含義

 * @Scheduled(cron = "0/5 * * * * ?") //每隔5s執(zhí)行一次
 * @Scheduled(fixedDelay = 5000) //上一次執(zhí)行完畢時(shí)間點(diǎn)之后5秒再執(zhí)行
 * @Scheduled(fixedDelayString = "5000") //上一次執(zhí)行完畢時(shí)間點(diǎn)之后5秒再執(zhí)行
 * @Scheduled(fixedRate = 5000) //上一次開始執(zhí)行時(shí)間點(diǎn)之后5秒再執(zhí)行
 * @Scheduled(initialDelay=1000, fixedRate=5000) //第一次延遲1秒后執(zhí)行纱注，之后按fixedRate的規(guī)則每5秒執(zhí)行一次

方式二：基于接口SchedulingConfigurer的動(dòng)態(tài)定時(shí)任務(wù)

image.png

package com.example.schedule.schedule;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.Trigger;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.SchedulingConfigurer;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.scheduling.config.ScheduledTaskRegistrar;
import org.springframework.scheduling.support.CronTrigger;
import org.springframework.util.StringUtils;

import java.util.Arrays;
import java.util.List;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;

@Configuration
@EnableScheduling
public class DynamicSchedule implements SchedulingConfigurer {


    /**
     * 測試數(shù)據(jù)，實(shí)際可從數(shù)據(jù)庫獲取
     */
    private List<Task> tasks = Arrays.asList(
            new Task(1, "任務(wù)1", "*/3 * * * * *"),
//            new Task(2, "任務(wù)2", "*/3 * * * * *"),
//            new Task(3, "任務(wù)3", "*/3 * * * * *"),
//            new Task(4, "任務(wù)4", "*/3 * * * * *"),
//            new Task(5, "任務(wù)5", "*/3 * * * * *"),
//            new Task(6, "任務(wù)6", "*/3 * * * * *"),
//            new Task(7, "任務(wù)7", "*/3 * * * * *"),
//            new Task(8, "任務(wù)8", "*/3 * * * * *"),
//            new Task(9, "任務(wù)9", "*/3 * * * * *"),
            new Task(10, "任務(wù)10", "*/3 * * * * *")
    );

    @Override
    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {
        scheduledTaskRegistrar.setScheduler(taskScheduler());

        tasks.forEach(task -> {
            //任務(wù)執(zhí)行線程
            Runnable runnable = () -> {
                System.out.println("execute task :" + task.getId());
                System.out.println(Thread.currentThread());
            };

            //任務(wù)觸發(fā)器
            Trigger trigger = triggerContext -> {
                //獲取定時(shí)觸發(fā)器，這里可以每次從數(shù)據(jù)庫獲取最新記錄，更新觸發(fā)器，實(shí)現(xiàn)定時(shí)間隔的動(dòng)態(tài)調(diào)整
                CronTrigger cronTrigger = new CronTrigger(task.getCron());
                return cronTrigger.nextExecutionTime(triggerContext);
            };

            //注冊任務(wù)
            scheduledTaskRegistrar.addTriggerTask(runnable, trigger);
        });

        //1
//        scheduledTaskRegistrar.addCronTask(new Runnable() {
//
//            @Override
//            public void run() {
//                log.warn(name+" --- > 開始");
//                //業(yè)務(wù)邏輯
//                log.warn(name+" --- > 結(jié)束");
//            }
//        }, cron);  //加入時(shí)間
    }

    /**
     * 設(shè)置TaskScheduler用于注冊計(jì)劃任務(wù)
     *
     * @return
     */
    @Bean
    public Executor taskScheduler() {
        ThreadPoolTaskScheduler t = new ThreadPoolTaskScheduler();
        t.setPoolSize(2);
        t.setThreadNamePrefix("taskScheduler - ");
        t.initialize();
        return t;
    }

    static class Task {
        /**
         * 主鍵ID
         */
        private int id;
        /**
         * 任務(wù)名稱
         */
        private String name;
        /**
         * cron表達(dá)式
         */
        private String cron;

        public Task(int id, String name, String cron) {
            this.id = id;
            this.name = name;
            this.cron = cron;
        }

        public int getId() {
            return id;
        }

        public void setId(int id) {
            this.id = id;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getCron() {
            return cron;
        }

        public void setCron(String cron) {
            this.cron = cron;
        }
    }
}