Inner and Nested Classes: Local 3

/**
 *  This code is from the book:
 *    David Glanagan: Java in a Nutshell 
 *    O'Reilly, Sept. 1997
 *  It is copyright (c) 1997 David Flanagan
 */

import java.util.*;
public class l1Lock3{//LinkedList

  //Top level nested interface, body elided
  public interface Linkable{....}

  //List head
  private Linkable head;

  //Other methods
  public void addToHead(Linkable node){...}
  public Linkable removeHead(){...}

  //Enumeration object for this linked list
  public Enumeration enumerate(){
    //Local class
    class Enumerator implements Enumeration{
      Linkable current;
      public Enumerator(){ 
	    this.current=LinkedList.this.head;
      }
      public boolean hasMoreElements(){ 
        return(current != null);
	  }
      public Object nextElement(){
        if (current == null) 
          throw new NoSuchElementException(``LinkedList'');
        Object value = current;
        current = current.getNext();
        return value;
      }
    }  
    return new Enumerator(); 
		//instance of Local Enumerator class 
  }
}