Java Programming question:

Develop an online store which sells dvds and books execpt this time,

we will also be selling AudioBooks which are specialized versions of Books (i.e., extension will come into play here). Use of multiple classes is a must for this Assignment and the perspective will be that of a store owner maintaining a Catalog.

The updated requirements for entities are as follows:

• Each CatalogItem has a title of type String.
• Each CatalogItem has a price of type double.
• Each Book (is a CatalogItem) has an author which is of type String.
• Each Book has an ISBN number which is of type int. Every book has a unique ISBN number.
• Each AudioBook has all of the properties of a Book, and in addition has a property named

runningTime of type double (conceptually you can think of this as minutes, but it doesn't matter

for the purposes of the assignment).

• Each DVD (is a CatalogItem) has director which is of type String.
• Each DVD has a year which is of type int.
• Each DVD has an dvdcode which is of type int and is unique for all DVDs.

Each of the properties is mandatory (cannot be a default) and private, and only retrieved via public getter methods (for example: getPrice which would return the price of a Book or DVD), and the properties can only be set via constructor functions.

Additionally, AudioBooks are special - when the price is retrieved via the method getPrice, the method in

the parent (Book) class is overridden, and instead the price is retrieved as the regular price of the book with a 10% discount (i.e., 90% of the price).

Each of the classes must define a toString method which *returns* information about the entity as follows:

For Books it would be:

Title: