???????
<dependencies>
    <!--spring boot核心-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>
    <!--spring boot 測試-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

@SpringBootApplication
@EnableScheduling
public class ScheduleApplication {
    public static void main(String[] args) {
        SpringApplication.run(ScheduleApplication.class, args);
    }
}

@Component
public class SchedulerTask {
    private static final Logger log = LoggerFactory.getLogger(SchedulerTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    /**
     * fixedRate：固定速率執(zhí)行。每5秒執(zhí)行一次。
     */
    @Scheduled(fixedRate = 5000)
    public void runWithFixedRate() {
        log.info("Fixed Rate Task，Current Thread : {}，The time is now : {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
    }
}

@Component
public class SchedulerTask {
    private static final Logger log = LoggerFactory.getLogger(SchedulerTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    /**
     * fixedDelay：固定延遲執(zhí)行。距離上一次調用成功后2秒后再執(zhí)行。
     */
    @Scheduled(fixedDelay = 2000)
    public void runWithFixedDelay() {
        log.info("Fixed Delay Task，Current Thread : {}，The time is now : {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
    }
}

@Component
public class SchedulerTask {
    private static final Logger log = LoggerFactory.getLogger(SchedulerTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    /**
     * initialDelay:初始延遲。任務的第一次執(zhí)行將延遲5秒，然后將以5秒的固定間隔執(zhí)行。
     */
    @Scheduled(initialDelay = 5000, fixedRate = 5000)
    public void reportCurrentTimeWithInitialDelay() {
        log.info("Fixed Rate Task with Initial Delay，Current Thread : {}，The time is now : {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
    }
}

@Component
public class SchedulerTask {
    private static final Logger log = LoggerFactory.getLogger(SchedulerTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    /**
     * cron：使用Cron表達式。每6秒中執(zhí)行一次
     */
    @Scheduled(cron = "*/6 * * * * ?")
    public void reportCurrentTimeWithCronExpression() {
        log.info("Cron Expression，Current Thread : {}，The time is now : {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
    }
}

@Component
public class AsyncScheduledTask {
    private static final Logger log = LoggerFactory.getLogger(AsyncScheduledTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    @Scheduled(fixedRate = 2000)
    public void runWithFixedDelay() {
        try {
            TimeUnit.SECONDS.sleep(3);
            log.info("Fixed Delay Task, Current Thread : {} : The time is now {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
        } catch (InterruptedException e) {
            log.error("錯誤信息",e);
        }
    }
}

@Component
@EnableAsync
public class AsyncScheduledTask {
    private static final Logger log = LoggerFactory.getLogger(AsyncScheduledTask.class);
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    @Async
    @Scheduled(fixedDelay = 2000)
    public void runWithFixedDelay() {
        try {
            TimeUnit.SECONDS.sleep(3);
            log.info("Fixed Delay Task, Current Thread : {} : The time is now {}", Thread.currentThread().getName(), dateFormat.format(new Date()));
        } catch (InterruptedException e) {
            log.error("錯誤信息",e);
        }
    }
}

@Configuration
public class SchedulerConfig implements SchedulingConfigurer {
    @Override
    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {
        ThreadPoolTaskScheduler threadPoolTaskScheduler = new ThreadPoolTaskScheduler();
        //線程池大小為10
        threadPoolTaskScheduler.setPoolSize(10);
        //設置線程名稱前綴
        threadPoolTaskScheduler.setThreadNamePrefix("scheduled-thread-");
        //設置線程池關閉的時候等待所有任務都完成再繼續(xù)銷毀其他的Bean
        threadPoolTaskScheduler.setWaitForTasksToCompleteOnShutdown(true);
        //設置線程池中任務的等待時間，如果超過這個時候還沒有銷毀就強制銷毀，以確保應用最后能夠被關閉，而不是阻塞住
        threadPoolTaskScheduler.setAwaitTerminationSeconds(60);
        //這里采用了CallerRunsPolicy策略，當線程池沒有處理能力的時候，該策略會直接在 execute 方法的調用線程中運行被拒絕的任務；如果執(zhí)行程序已關閉，則會丟棄該任務
        threadPoolTaskScheduler.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        threadPoolTaskScheduler.initialize();
        scheduledTaskRegistrar.setTaskScheduler(threadPoolTaskScheduler);
    }
}