每一秒都做点什么

Timer timer = new Timer();
timer.schedule(new TimerTask() {
    @Override
    public void run() {
        //code
    }
}, 0, 1000);

你应该看看Quartz，它是一个java框架，适用于EE和SE版本，并允许定义作业来执行特定的时间

这两个类可以一起工作来安排一个周期性任务:

计划任务

import java.util.TimerTask;
import java.util.Date;

// Create a class extending TimerTask
public class ScheduledTask extends TimerTask {
    Date now; 
    public void run() {
        // Write code here that you want to execute periodically.
        now = new Date();                      // initialize date
        System.out.println("Time is :" + now); // Display current time
    }
}

运行定时任务

import java.util.Timer;

public class SchedulerMain {
    public static void main(String args[]) throws InterruptedException {
        Timer time = new Timer();               // Instantiate Timer Object
        ScheduledTask st = new ScheduledTask(); // Instantiate SheduledTask class
        time.schedule(st, 0, 1000);             // Create task repeating every 1 sec
        //for demo only.
        for (int i = 0; i <= 5; i++) {
            System.out.println("Execution in Main Thread...." + i);
            Thread.sleep(2000);
            if (i == 5) {
                System.out.println("Application Terminates");
                System.exit(0);
            }
        }
    }
}

参考https://www.mkyong.com/java/how-to-run-a-task-periodically-in-java/

我使用Spring Framework的特性。(spring-context jar或maven依赖)。

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;


@Component
public class ScheduledTaskRunner {

    @Autowired
    @Qualifier("TempFilesCleanerExecution")
    private ScheduledTask tempDataCleanerExecution;

    @Scheduled(fixedDelay = TempFilesCleanerExecution.INTERVAL_TO_RUN_TMP_CLEAN_MS /* 1000 */)
    public void performCleanTempData() {
        tempDataCleanerExecution.execute();
    }

}

ScheduledTask是我自己与自定义方法execute的接口，我将其作为我的计划任务调用。

如果您的应用程序已经在使用Spring框架，那么您已经内置了调度

使用谷歌Guava AbstractScheduledService如下所示:

public class ScheduledExecutor extends AbstractScheduledService {

   @Override
   protected void runOneIteration() throws Exception {
      System.out.println("Executing....");
   }

   @Override
   protected Scheduler scheduler() {
        return Scheduler.newFixedRateSchedule(0, 3, TimeUnit.SECONDS);
   }

   @Override
   protected void startUp() {
       System.out.println("StartUp Activity....");
   }


   @Override
   protected void shutDown() {
       System.out.println("Shutdown Activity...");
   }

   public static void main(String[] args) throws InterruptedException {
       ScheduledExecutor se = new ScheduledExecutor();
       se.startAsync();
       Thread.sleep(15000);
       se.stopAsync();
   }
}

如果你有更多这样的服务，那么在ServiceManager中注册所有的服务会很好，因为所有的服务都可以同时启动和停止。阅读这里了解更多关于ServiceManager的信息。