Java - How to run a task periodically

In this section, we will show you how to run a task periodically in Java.

1. ScheduledTask.java

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

// Create a class extends with TimerTask
public class ScheduledTask extends TimerTask {

   // to display current time
    Date now;

   // Add your task here
   public void run() {
      // initialize date
      now = new Date();
      // Display current time
      System.out.println("Time is :" + now);
   }
}

2. Run Scheduler Task

A class to run above scheduler task.

import java.util.Timer;

//Main class
public class SchedulerMain {
   public static void main(String args[]) 
         throws InterruptedException {

      // Instantiate Timer Object
      Timer time = new Timer();
      // Instantiate SheduledTask class
      ScheduledTask st = new ScheduledTask();
      // Create Repetitively task for every 2 secs
      time.schedule(st, 0, 2000);

      //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);
         }
      }
   }
}

Console Output:
Time is :Fri Jan 20 23:13:15 IST 2023
Execution in Main Thread....0
Time is :Fri Jan 20 23:13:17 IST 2023
Execution in Main Thread....1
Time is :Fri Jan 20 23:13:19 IST 2023
Execution in Main Thread....2
Time is :Fri Jan 20 23:13:22 IST 2023
Execution in Main Thread....3
Time is :Fri Jan 20 23:13:24 IST 2023
Execution in Main Thread....4
Time is :Fri Jan 20 23:13:26 IST 2023
Execution in Main Thread....5
Time is :Fri Jan 20 23:13:28 IST 2023
Application Terminates

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