@Scheduled多个任务同时开始执行

只需在springBoot启动类上添加

如下代码即可：

@Bean
public TaskScheduler taskScheduler() {
    ThreadPoolTaskScheduler taskExecutor = new ThreadPoolTaskScheduler();
    taskExecutor.setPoolSize(50);
    return taskExecutor;
}

@Scheduled多定时任务，重叠执行

@Scheduled如果有两个定时任务

定时任务重复时，只有一个可以执行。

如下

import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component; 
import java.time.LocalDateTime;
  
@Component
public class MyScheduled { 
    @Scheduled(cron = "0/5 * * * * ?")
    public void execute1(){
        String curName = Thread.currentThread().getName() ;
        System.out.println("当前时间:"+LocalDateTime.now()+"  任务execute1对应的线程名: "+curName);
        try {
            Thread.sleep(1000);
        } catch (Exception e) {
            e.printStackTrace();
        } 
    }
  
    @Scheduled(cron = "0/5 * * * * ?")
    public void execute2(){ 
        String curName = Thread.currentThread().getName() ;
        System.out.println("当前时间:"+LocalDateTime.now()+"  任务execute2对应的线程名: "+curName);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

通过执行可以看到，打印线程名称为同一个。即如果不手动指定线程池，则默认启动单线程，进行执行定时任务。

如果想要多个定时任务重叠执行

需要手动指定线程池，如下

import org.springframework.context.annotation.Bean;
import org.springframework.scheduling.TaskScheduler;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.stereotype.Component; 
import java.time.LocalDateTime;
  
@Component
@EnableScheduling
public class MyScheduled {
  
    @Bean
    public TaskScheduler taskScheduler() {
        ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler();
        taskScheduler.setPoolSize(50);
        return taskScheduler;
    }
  
    @Scheduled(cron = "0/5 * * * * ?")
    public void execute1(){
        String curName = Thread.currentThread().getName() ;
        System.out.println("当前时间:"+LocalDateTime.now()+"  任务execute1对应的线程名: "+curName);
        try {
            Thread.sleep(1000);
        } catch (Exception e) {
            e.printStackTrace();
        } 
    }
  
    @Scheduled(cron = "0/5 * * * * ?")
    public void execute2(){ 
        String curName = Thread.currentThread().getName() ;
        System.out.println("当前时间:"+LocalDateTime.now()+"  任务execute2对应的线程名: "+curName);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

此时，多个定时任务，是不通的线程执行，同时，定时任务可以重叠执行。