Creating and Running a Daemon Thread

CleanerTask.java

import java.util.Date;
import java.util.Deque;

public class CleanerTask extends Thread {

   private Deque<Event> deque;

   public CleanerTask(Deque<Event> deque) {
      this.deque = deque;
      // Establish that this is a Daemon Thread
      setDaemon(true);
   }

   @Override
   public void run() {
      while (true) {
         Date date = new Date();
         clean(date);
      }
   }

   private void clean(Date date) {
      long difference;
      boolean delete;
      if (deque.size() == 0) {
         return;
      }

      delete = false;
      do {
         Event e = deque.getLast();
         difference = date.getTime() - e.getDate().getTime();
         if (difference > 10000) {
            System.out.printf("Cleaner: %s\n", e.getEvent());
            deque.removeLast();
            delete = true;
         }
      } while (difference > 10000);

      if (delete) {
         System.out.printf("Cleaner: Size of the queue: %d\n", deque.size());
      }
   }
}

Event.java

import java.util.Date;

public class Event {

   private Date date;

   private String event;

   public Date getDate() {
      return date;
   }

   public void setDate(Date date) {
      this.date = date;
   }

   public String getEvent() {
      return event;
   }

   public void setEvent(String event) {
      this.event = event;
   }
}

Main.java

// Creating and running a daemon thread

import java.util.Deque;
import java.util.concurrent.ConcurrentLinkedDeque;

public class Main {

   public static void main(String[] args) {

      // Creates the Event data structure
      Deque<Event> deque = new ConcurrentLinkedDeque<>();

      // Creates the three WriterTask and starts them
      WriterTask writer = new WriterTask(deque);
      for (int i = 0; i < Runtime.getRuntime().availableProcessors(); i++) {
         Thread thread = new Thread(writer);
         thread.start();
      }

      // Creates a cleaner task and starts them
      CleanerTask cleaner = new CleanerTask(deque);
      cleaner.start();

   }

}

WriterTask.java

import java.util.Date;
import java.util.Deque;
import java.util.concurrent.TimeUnit;

public class WriterTask implements Runnable {

   Deque<Event> deque;

   public WriterTask(Deque<Event> deque) {
      this.deque = deque;
   }

   @Override
   public void run() {

      // Writes 100 events
      for (int i = 1; i < 100; i++) {
         // Creates and initializes the Event objects
         Event event = new Event();
         event.setDate(new Date());
         event.setEvent(
               String.format("The thread %s has generated the event %d event", Thread.currentThread().getId(), i));

         // Add to the data structure
         deque.addFirst(event);
         try {
            // Sleeps during one second
            TimeUnit.SECONDS.sleep(1);
         } catch (InterruptedException e) {
            e.printStackTrace();
         }
      }
   }
}