//jleblanc 5.3.06
//PAC
//This Class Authored by Michael Lewis

import java.util.Vector;

public class Queue extends Vector
{
   /** Creates a new instance of the Queue class. */
   public Queue() {}

   /**
    * Adds an object to the queue.
    */
   public void enqueue(Object item)
   {
       addElement(item);
   }

   /**
    * Removes an object from the queue.
    */
   public synchronized Object dequeue()
   {
       Object obj = null;
       if (size() > 0) {
           obj = firstElement();
           removeElementAt(0);
       }
       return obj;
   }

   /**
    * Checks whether the queue is empty.
    */
   public boolean isEmpty()
   {
       return size() == 0;
   }
}