//  Linked list example from Lewis and Loftus, page 500

class Book {

   private String title;

   public Book (String newTitle) {    
      title = newTitle; 
   }

   public String toString () {
      return title; 
   }
}

class BookList {

   private BookNode list; 

   public BookList() {
      list = null; 
   }

// Creates and adds a new Book object to the end of list

   public void add (Book newBook) {

      BookNode node = new BookNode (newBook);
      BookNode current;

      if (list == null)
         list = node;
      else  {
         current = list;
         while (current.next != null)
            current = current.next;
         current.next = node;
      }
   }

   public String toString ()  {

      String result = "";
      BookNode current = list;

      while (current != null)  {
         result += current.book.toString() + "\n";
         current = current.next;
      }

      return result;
   }

//  An inner class that represents a node in list

   private class BookNode {

      public Book book;
      public BookNode next;

      public BookNode (Book theBook) {
         book = theBook;
         next = null; 
      }
   }
}

public class Library {
   
   public static void main (String[] args) {
    
      BookList books = new BookList();
      
      books.add (new Book("The Hitchhiker's Guide to the Galaxy"));
      books.add (new Book("Jonathan Livingston Seagull"));
      books.add (new Book("A Tale of Two Cities"));
      books.add (new Book("Java Software Solutions"));
      
      System.out.println (books); 
   }
}