//<PLAINTEXT>
import java.util.*;

/**
 * LLQueue.java<br>
 * A queue implementation that extends java.util.LinkedList<p>
 *
 * Created: Tue Mar 25 13:24:26 2003
 *
 * @author <a href="mailto:shapiro@cse.buffalo.edu">Stuart C. Shapiro</a>
 */

public class LLQueue extends LinkedList {
    /**
     * Creates a new <code>LLQueue</code> instance.
     *
     */
    public LLQueue (){
	super();
    }

    /**
     * Returns the first element on this queue.
     *
     * @return the first <code>Object</code> on the queue.
     * @exception NoSuchElementException if this queue is empty.
     */
    public Object front() throws NoSuchElementException {
	return getFirst();
    }

    /**
     * Adds an <code>Object</code> to the rear of this queue.
     *
     * @param obj the <code>Object</code> to be added to this queue.
     */
    public void enqueue(Object obj) {
	addLast(obj);
    }

    /**
     * Removes the <code>Object</code> that is at the front of this
     * queue, and returns it.
     *
     * @return the <code>Object</code> at the front of this queue,
     * having removed it from this queue.
     * @exception NoSuchElementException if this queue is empty.
     */
    public Object dequeue() throws NoSuchElementException{
	return removeFirst();
    }

}// LLQueue