Assignment 2 (100 Pts)

Due: Thursday, June 22

Using Inheritance

In this assignment, you will create 4 classes that could be used to maintain a database of media items in a library or that an individual owns. These classes will represent generic media items, CDs, DVDs, and books on tape. You will also write a driver program that uses these classes and illustrates polymorphism.

All media items have the following characteristics:

a title
a variable to track if that item is currently present in the collection
a playing time
a copyright date

All media items have the following behaviors:

get the title
get the copyright year
get if the item is present in the collection
set the status of the item, in or out of the collection
get the playing time; it may be useful to get this information in several formats, for example in minutes or in hours and minutes
a toString method (or course! it is an Object!)
be Comparable

CDs, DVDs, and books on tape have all of the characteristics and behaviors of media items.

CDs have the following additional characteristics and behaviors:

an artist
a number of tracks
a way to get the artist
a way to get the number of tracks

DVDs have the following additional characteristics and behaviors:

a rating, e.g., G, PG PG-13, R, NC-17. These examples are from the MPAA ratings system. There are different ratings systems in other countries so use a String for the rating. What would be an appropriate way to represent these ratings?
a length of time for the bonus features
a way to get the rating
a way to get the time of the bonus features
a way to get the total playing time of the DVD. (Note this should override MediaItem's method for getting the playing time.)

Books on tape have the following additional characteristics and behaviors:

an author
a narrator
a way to get the author
a way to get the narrator

You are to implement four classes, MediaItem, CD, DVD, and BookOnTape. CD, DVD, and BookOnTape must all extend MediaItem. You must provide at least one constructor for each class that takes parameters to set all instance variables. You should make all the instance variables private in all classes. You are not to repeat instance variables from MediaItem in the classes that extend it. You will have to override some of the methods in MediaItem in the various sub classes, as appropriate.

A driver program

To test your classes, you will write a driver program that uses these. (Of course, you will test each of your classes along the way too, right?)

The driver program emulates a library that keeps track of all the media that is in the library. Your driver program will

Create at least two instances of each type of media
Store the instances in an array
Sort the array
Exercise the accessor and mutator methods of the objects (check item into or out of the library)
Print out all pertinent information about each item in the library, e.g., if the item is in or out of the library

Your driver program may need to provide some utilities to handle initializing the objects.

When you execute your program, demonstrate your program's ability to handle strange or incorrect behavior as well.

Packages

The prefix to your Java class's package for all assignments will be your last name followed by the assignment name. For example, my package name's prefix would be sprenkle.assign2. (Remember what this means for the directory structure of your classes.) You can have additional packages underneath this prefix. For example, the full package for my assignment could be sprenkle.assign2.library.media

Java Docs

Generate Java Docs for all of your classes, including your driver program. You may find it useful to refer to these while you're developing too.

You will submit your final HTML Java Docs too, on paper and electronically. Do NOT print out the raw HTML code (e.g.,

<html>
<body>
...

Load the HTML documentation for your classes up in a browser and print from there. Print the package summary page as well as the documentation for each individual class.

README

Your README file should contain

Your name
Assignment name
Date
High-level description of the assignment and what your program(s) does
A list of submitted files
The online location of your Java Docs, e.g., http://copland.udel.edu/~sprenks/cisc370/docs. (This is just an example location; the docs at the location are not complete.)
Instructions for running your program
Any other information you want Ke or Sara to know

Script file

Create a script file showing your README, your code, compilation, and execution of your program.

If you use Eclipse to run your program, you can copy the text in the Console window from your program's execution and pastes it into Notepad, or some other form that you can save and print. Or, you can upload (ftp) your code to strauss and use the script command there. Eclipse is just a development environment. Java is portable, so you should be able to run your code on any machine that has a JVM.

Submission

Submit a printed version of your assignment (script file, Java files, Java Docs, and README) at the beginning of class on Thursday, June 22.

Electronic Submission Organization

Your submission directory will look something like this:

sprenkle/
- assign2/
  - CD.class
  - CD.java
  - DVD.class
  - DVD.java
  - ...
  - README
  - assign2.script
  - docs/ (the HTML documentation)

Email a gzipped tar file of your assignment directory (named lastname, as shown above), which includes the script file, the Java files, the class files, the docs, and README to Ke (kli at cis.udel.edu) before next Thursday (June 22) at 11:59:59 p.m. The name of your zipped submission should be lastname-assign2.tar.gz (or .zip or whatever the appropriate extension). The subject line should be "[Your Name] CISC370: Assignment 2 Submission".

If necessary, see Assignment 0 for instructions for generating the tar file.

If you have any questions about submission, ask early!

We will follow similar directory structures in future submissions.

Grading (100 pts)

Correctness (classes, driver): 40 pts
Organization (inheritance relationships): 20 pts
Testing (as demonstrated in script file): 30 pts
Documentation (completeness, correctness): 10 pts

This problem is based on a similar example from Objects First With Java by David Barnes and Michael Kolling.