ScheduledTask.java

package com.taskscheduler;

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

/**
 * Schedules tasks to run after a delay or at a fixed rate,
 * then submits them into the custom ThreadPool for execution.
 */
public class ScheduledTask {

    private final ThreadPool threadPool;
    private final ScheduledExecutorService scheduler;

    public ScheduledTask(ThreadPool threadPool) {
        this.threadPool = threadPool;
        this.scheduler  = Executors.newSingleThreadScheduledExecutor(r -> {
            Thread t = new Thread(r, "Scheduler");
            t.setDaemon(true);
            return t;
        });
    }

    /**
     * Submit a task to the pool after a fixed delay.
     */
    public void scheduleOnce(String name, Runnable runnable, long delay, TimeUnit unit) {
        scheduler.schedule(() -> {
            System.out.printf("[Scheduler] Firing delayed task: %s%n", name);
            threadPool.submit(name, runnable);
        }, delay, unit);
    }

    /**
     * Submit a task to the pool repeatedly at a fixed rate.
     */
    public void scheduleRepeating(String name, Runnable runnable, long initialDelay,
                                   long period, TimeUnit unit) {
        scheduler.scheduleAtFixedRate(() -> {
            System.out.printf("[Scheduler] Firing repeating task: %s%n", name);
            threadPool.submit(name, runnable);
        }, initialDelay, period, unit);
    }

    public void shutdown() {
        scheduler.shutdown();
    }
}