IS 313 Individual Assignment 2

IS 313: Data Structures in Java

Autumn 2002

Individual Assignment 2

Using collection classes and iterators

Due Friday October 11 before 11:30pm

Sometimes not-for-profit institutions need to know more about their donors than simply who are the largest donors. For example, it may be useful to know where the biggest donors live or why they made donations. For this next assignment, you will work on an expanded version of the program from the last assignment. First, you will write an expanded Donations class that reads and updates the donations file. Second, you will work on a new class that reads in an expanded names file that includes the donor's city and what plays he or she attended. This information will allow your program to present donation totals by city or by play. Finally, you will write a simple interface that allows a user to interact with the program.

Part 1

Create a new class called SavedDonations that extends the Donations class. This class should provide two new methods:

read -- This method takes a file name (a string) and reads in the specified donations file. It should also save the file name for the write method.
write -- Without an argument, this method saves the updated donations list to the same file that the donations list was read from. With a string argument, it writes the donations list to the file named by the argument.

Because the Donations class does not keep a record of each individual donation, your extended class must store each donation (i.e. the ID and the amount) as it is read in or added to the list. This way, it can then write all donations back to the file when the write method is called. In order to store all donations, you need to override the addDonation method so that it saves all donations.

Additional requirements (really hints)

Use List objects to store the IDs and donation amounts as they are being added to the donations collection.
Your addDonations method should call the addDonations method of the Donations class (super.addDonations) after it has stored the donation.
The write method without the argument should call the write method with the filename argument.
Write test code for this class and place it in its main method.

Part 2

The names file has been expanded to include the donor's city and which plays the donor attended. Here's an example of the names file using the new format:

  Jones, Sam
  2
  Chicago
  The Miser&Tartuffe
  Smith, Alfred
  3
  Oak Park
  The Miser&The Imaginary Invalid
  Miller, Andrew
  5
  Evanston
  Tartuffe

Note that the play titles are separated by the '&' character since play titles may have spaces in them.

Using the newly formatted names file, create a class called DonorCollection that reads in this file and provides the following methods for accessing useful information:

read -- This method takes a string specifying the file name. It reads in all of the information in the newly formatted names file.
getName -- This method takes an integer that specifies a donor's ID. It returns the name that corresponds to the ID or returns null if the donor is not listed in the names file.
getCities -- This method returns a Set that includes all of the cities the donors are from.
getPlays -- This method returns a Set that includes all of the plays the donors attended.
getTotalByCity -- This method takes a Donations object and a string specifying a city. It returns the total amount of the donations from donors living in the specified city.
getTotalByPlay -- This method takes a Donations object and a string specifying a play. It returns the total amount of the donations from donors who attended the specified play.

Additional requirements (really hints)

The Donor class constructs objects that hold a donor's name, id, city and plays attended. Use its objects to store the contents of the names file.
So that the donor's name can be referenced efficiently, use a Map that links a donor's ID (represented as an Integer object) to each Donor object.
A skeleton of the DonorCollection class is created for you. It already has some methods written for you. You need to finish the remaining methods and complete the comments.

Part 3

Write a simple driver class called DonorAdmin that uses the SavedDonations class and the DonorCollection class. This class should provide simple user interaction through command-line menus that allow a user to do the following items:

Update the donations list
Obtain donation totals by city and by play
Obtain donor lists sorted by number and total amount (like assignment 1)
Obtain a donor's name given the donor's ID.

Example data files

Here are example data files for donations and names. You should find that the larger cities (e.g. Chicago) generally have larger donation totals. You will also find that one of the plays has produced larger donation totals too.

Submission

Before the due date and time, you should submit the following files through the submission Web page:

SavedDonations.java
DonorCollection.java
DonorAdmin.java

If for some reason you are unable to submit the files, you may email me them as an attachment.