Why is it best to use super?

A good answer might be:

You should not write the same code more than once. You might make a mistake the second time (for example: forgetting to initialize the member avail.)

Here is an example program that makes use of the two classes:

class TapeStore { public static void main ( String args[] ) { VideoTape item1 = new VideoTape("Microcosmos", 90 ); Movie item2 = new Movie("Jaws", 120, "Spielberg", "PG" ); item1.show(); item2.show(); } }

(You can run this program by using NotePad and copying and pasting the class definitions from the previous pages.) When you run it, you will get the following output:

Microcosmos, 90 min. available:true
Jaws, 120 min. available:true

The statement item2.show() calls the show() method of item2. This method was inherited without change from the class VideoTape. This is what it looks like:

public void show() { System.out.println( title + ", " + length + " min. available:" + avail ); }

It does not mention the new variables that have been added to objects of type Movie, so nothing new is printed out.

QUESTION 11:

Why not change show() in VideoTape to include the line

    System.out.println( "dir: " + director + rating );