class PrinterQueue

{

   private final Lock queueLock = new ReentrantLock();

   public void printJob(Object document)

   {

      queueLock.lock();

      try

      {

         Long duration = (long) (Math.random() * 10000);

         System.out.println(Thread.currentThread().getName() + ": PrintQueue: Printing a Job during " + (duration / 1000) + " seconds :: Time - " + new Date());

         Thread.sleep(duration);

      } catch (InterruptedException e)

      {

         e.printStackTrace();

      } finally

      {

         System.out.printf("%s: The document has been printed\n", Thread.currentThread().getName());

         queueLock.unlock();

      }

   }

}