// An example of using Inheritance, Overloading and polymorphism

/** Our good old book class */
class Book {
  protected String title; /* notice that these are */
  protected int npages;   /* now protected, not private */
  
  public Book() { // Default constructor
    title = "No title"; npages = 0;
  }
  
  /** A second constructor */
  public Book(String booktitle, int pages) {
    title = booktitle; npages = pages;
  }
  
  /** A public method */
  public void Read(int pagestart, int pageend) {
    if (pageend < npages) {
      System.out.println("Reading "+ title + " from page " +
			 pagestart + " to " + pageend);
    }
    else {
      System.out.println("Give me another book!");
    }
  }
}

/** The first subclass - hardly anything extra, just to show things */
class ComicBook extends Book {
  public ComicBook(String booktitle, int pages) {
    title = booktitle; /* title is not in this class - INHERITED */
    npages = pages;    /* likewise */
  }

}

class TextBook extends Book {
  private String Course;

  public TextBook(String booktitle, int pages, String incourse) {
    super(booktitle, pages);
    Course = incourse;
  }

  public void Read(int pagestart, int pageend) {
    System.out.println(Course + "has a very dull textbook!");
  }
}

public class BookReader {
  
  public static void main(String[] args) {

    // create a new Comic Book
    ComicBook favoriteComic = new ComicBook("Yukon Ho!", 85); 
    favoriteComic.Read(75, 95); // Read is not in ComicBook, still works!
				// *** Inheritance ***

    // create a new text book, but assign it to a variable of tyep Book!
    // *** Polymorphism ***
    Book a201Text = new TextBook("CCJ", 625, "A201");
    a201Text.Read(475, 525); // This time use the overloaded Read
				// method in Textbook.
				// *** Overloading ***
    
  }
}