Java - Thread scheduling using Scheduled Thread Pool Executor

The below Java class demonstrates the periodic scheduling of Threads using Scheduled Thread Pool Executor.

public class WorkerThread implements Runnable
{
        private String  threadName      = null;

        public WorkerThread(String threadName)
        {
                this.threadName = threadName;
        }

        public void run()
        {
                System.out.println(this.threadName + " started...");
                try
                {
                        Thread.sleep(5000);
                }
                catch (InterruptedException e)
                {
                        e.printStackTrace();
                }
                System.out.println(this.threadName + " ended...");
        }
}

import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * This class demonstrates the usage of Scheduled Thread Pool executor
 *  
 * @author TechDive
 */

public class MainThread
{
        public static void main(String[] args)
        {
                int corePoolSize = 2;
                ScheduledThreadPoolExecutor stpe = new ScheduledThreadPoolExecutor(corePoolSize);

                /*
                 * This will execute the WorkerThread immediately
                 */

                stpe.execute(new WorkerThread("WorkerThread-Running-Immediately"));

                /*
                 * This will execute the WorkerThread only once after 10 Seconds
                 */

                stpe.schedule(new WorkerThread("WorkerThread-Scheduled-After-10-seconds"), 10, TimeUnit.SECONDS);

                /*
                 * This will execute the WorkerThread continuously for every 5 seconds with an initial delay of 10
                 * seconds for the first WorkerThread to start execution cycle. In this case, whether the first
                 * WorkerThread is completed or not, the second WorkerThread will start exactly after 5 seconds hence
                 * called schedule at fixed rate. This continues till 'n' threads are executed.
                 */

                stpe.scheduleAtFixedRate(new WorkerThread("WorkerThread-Running-At-Fixed-Rate"), 10, 5, TimeUnit.SECONDS);

                /*
                 * This will execute the WorkerThread continuously with an initial delay of 10 seconds for the first
                 * WorkerThread to start execution cycle. Once the first thread execution completes then a delay of 5
                 * Seconds is introduced so that the next WorkerThread execution cycle starts. This continues till
                 * 'n' thread are executed. This is called schedule each thread with a fixed delay.
                 */

                stpe.scheduleWithFixedDelay(new WorkerThread("WorkerThread-Running-With-Fixed-Delay"), 10, 5, TimeUnit.SECONDS);
        }
}

Output :

WorkerThread-Running-Immediately started...
WorkerThread-Running-Immediately ended...
WorkerThread-Scheduled-After-10-seconds started...
WorkerThread-Running-At-Fixed-Rate started...
WorkerThread-Running-At-Fixed-Rate ended...
WorkerThread-Scheduled-After-10-seconds ended...
WorkerThread-Running-With-Fixed-Delay started...
WorkerThread-Running-At-Fixed-Rate started...
WorkerThread-Running-At-Fixed-Rate ended...
WorkerThread-Running-With-Fixed-Delay ended...
WorkerThread-Running-At-Fixed-Rate started...
WorkerThread-Running-At-Fixed-Rate ended...
WorkerThread-Running-At-Fixed-Rate started...
WorkerThread-Running-With-Fixed-Delay started...

<Thread execution continues...>

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