ScheduledExecutorService for Recurring Tasks

The ScheduledExecutorService interface is the standard way to run tasks at fixed intervals in modern Java. Unlike traditional timers, it utilizes a thread pool and provides robust control over task execution and life cycle management.

import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class TaskRunner {
    public static void main(String[] args) {
        // Initialize a single-threaded executor
        ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

        Runnable heartbeatTask = () -> {
            System.out.println("Task performed at timestamp: " + System.currentTimeMillis() / 1000);
        };

        // Schedule task: (Runnable, initialDelay, period, unit)
        executor.scheduleAtFixedRate(heartbeatTask, 0, 5, TimeUnit.SECONDS);
    }
}

Utilizing java.util.Timer

For simple or legacy applications, the java.util.Timer class offers a straightforward approach to scheduling background tasks. It is useful for basic scennarios where complex thread management is not required.

import java.util.Timer;
import java.util.TimerTask;

public class SimpleScheduler {
    public static void main(String[] args) {
        Timer jobTimer = new Timer();

        TimerTask recurringJob = new TimerTask() {
            @Override
            public void run() {
                System.out.println("Execution triggered every 5000ms");
            }
        };

        // Parameters: task, delay (ms), period (ms)
        long startDelay = 0L;
        long interval = 5000L;
        
        jobTimer.scheduleAtFixedRate(recurringJob, startDelay, interval);
    }
}

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