Description
The election manager is back, and we’re going to add a new flavor to it!
In P01, you maintained the election manager list by using an oversize array as an argument to some
utility methods, which trusted that the array was being correctly maintained according to oversize array
protocols – compact, and with an accurate size variable.
Now that we’ve unlocked object-oriented design, we’re going to encapsulate all of this election
management into a class, so we can be absolutely sure that it’s being maintained properly. If someone
tries to do something they’re not allowed to do, well, that’s what exceptions are for.
There will be some familiar pieces to this program but also some new functionality, so read the writeup
and the provided documentation carefully.
Grading Rubric
5 points Pre-assignment Quiz: accessible through Canvas until 11:59PM on 10/06.
+5% Bonus Points: students whose final submission to Gradescope is before 5:00 PM
Central Time on WED 10/09 and who pass ALL immediate tests will receive an
additional 2.5 points toward this assignment, up to a maximum total of 50 points.
20 points Immediate Automated Tests: accessible by submission to Gradescope. You will
receive feedback from these tests before the submission deadline and may make
changes to your code in order to pass these tests.
Passing all immediate automated tests does not guarantee full credit for the
assignment.
15 points Additional Automated Tests: these will also run on submission to Gradescope, but
you will not receive feedback from these tests until after the submission deadline.
10 points Manual Grading Feedback: TAs or graders will manually review your code, focusing
on algorithms, use of programming constructs, and style/readability.
50 points MAXIMUM TOTAL SCORE
Learning Objectives
After completing this assignment, you should be able to:
● Implement a simple object with basic accessor and mutator methods
● Communicate error states using exceptions and appropriate messages, and explain how to
appropriately handle thrown exceptions.
● Explain the different requirements of using a static vs. a non-static method
● Incorporate exception handling into your tester methods so that they can survive unusual
circumstances and receive communication about error states from other methods without
crashing
Additional Assignment Requirements and Notes
Keep in mind:
● Pair programming is ALLOWED for this assignment, BUT you must have registered your
partnership before this specification was released. If you did not do so, you must complete this
assignment individually.
● The ONLY external libraries you may use in your program are:
Election.java – java.util.NoSuchElementException
Ballot.java – java.util.ArrayList, java.util.NoSuchElementException
ElectionManagerTester.java – java.util.Arrays, any relevant exceptions
● Use of any other packages (outside of java.lang) is NOT permitted.
● You are allowed to define any local variables you may need to implement the methods in this
specification (inside methods). You are NOT allowed to define any additional instance or static
variables or constants beyond those specified in the write-up.
● You are allowed to define additional private helper methods.
● Only the ElectionManagerTester class may contain a main method.
● All classes and methods must have their own Javadoc-style method header comments in
accordance with the CS 300 Course Style Guide.
● Any source code provided in this specification may be included verbatim in your program
without attribution.
● All other sources must be cited explicitly in your program comments, in accordance with the
Appropriate Academic Conduct guidelines.
● Any use of ChatGPT or other large language models must be cited AND your submission MUST
include screenshots of your interactions with the tool clearly showing all prompts and
responses in full. Failure to cite or include your logs is considered academic misconduct and will
be handled accordingly.
● Run your program locally before you submit to Gradescope. If it doesn’t work on your
computer, it will not work on Gradescope.
Need More Help?
Check out the resources available to CS 300 students here.
CS 300 Assignment Requirements
You are responsible for following the requirements listed on both of these pages on all CS 300
assignments, whether you’ve read them recently or not. Take a moment to review them:
● Appropriate Academic Conduct, which addresses such questions as:
○ How much can you talk to your classmates?
○ How much can you look up on the internet?
○ How do I cite my sources?
○ and more!
● Course Style Guide, which addresses such questions as:
○ What should my source code look like?
○ How much should I comment?
○ and more!
Getting Started
1. Create a new project in Eclipse, called something like P04 Exceptional Elections
1
.
a. Ensure this project uses Java 17. Select “JavaSE-17” under “Use an execution
environment JRE” in the New Java Project dialog box.
b. Do not create a project-specific package; use the default package.
2. Download one (1) Java source file from the assignment page on Canvas:
a. ElectionManagerTester.java (includes a main method)
3. Create three (3) Java source files within that project’s src folder:
a. Ballot.java (does NOT include a main method)
b. Election.java (does NOT include a main method)
c. Candidate.java (does NOT include a main method)
1 Because we now have exceptions, you see.
1. Election Manager Tester
The ElectionManagerTester.java provided to you includes all REQUIRED tester methods, which are not
comprehensive. The only testers you are required to implement for this assignment are for the methods
which may throw exceptions.
You are welcome to add additional testers, but they must be private.
We’ve provided two fully-implemented tester methods. This program features some expected behavior
that involves throwing exceptions, and these two methods demonstrate how you should write testers to
validate that kind of behavior:
1. testCandidateConstructorAndGetters() demonstrates a tester for a method (a
constructor in this case) which should not throw an exception, but may throw one if it is poorly
implemented. In this case, if you catch any exceptions, you should consider the test to have
failed and return false.
2. testVoteExceptions() demonstrates a tester for a method which should throw an
exception, but may not throw one or may throw the wrong type of exception if poorly
implemented. In this case, if you do NOT catch an exception or if you catch the wrong type of
exception, you should consider the test to have failed and return false, but if you DO catch the
expected type of exception, that’s good!!
As with P01, we recommend writing at least one relevant test before you implement the class/method it
would test. We speak from experience here, as debugging 1 thing is WAY easier than debugging 10
things that all depend on each other.
2. The Candidate data type
Where P01 represented candidates as an array of 3 Strings, this program represents each candidate as its
own custom-defined object. In addition to the name (still a String) and party (also still a String), we’ll
now be tracking numVotes directly as an int.
Two candidates are considered the “same” in this version of the program if their name and party match
exactly AND if they have received the same number of votes. As part of this class, you will override
Object’s equals() method to recognize deep copy candidates as being equal – by default, equals()
only recognizes shallow copies.
We have also required you to add an implementation of toString() to Candidate, so that you can
easily and meaningfully print a Candidate object to the console. The format is:
name (party): numVotes
More information and additional methods can be found in the javadocs.
3. The Election data type
As in P01 this design uses a compact oversized array to hold all of our Candidates, but instead of relying
on the tester class to maintain the oversize arrays properly, you’ll encapsulate the relevant information
and methods in an object.
More information and a complete list of required methods can be found in the javadocs.
The compact, oversize candidates array must have nulls in elements not being used; for full credit you
must REMOVE all data not currently being used. For example, if numCandidates is 3 and
candidates.length is 7 then the array’s contents will be as follows:
{candidate1, candidate2, candidate3, null, null, null, null}
The name of the seat an election is for is a CONSTANT value associated with each Election object. This
means you must initialize that value in the constructor, or your code will not compile! Do not initialize
this value when you declare it; if you do so, every election will be for the same seat. However, since this
value is constant, we’ll make it public to skip the necessity of writing an accessor method for it.
We haven’t required a containsCandidate() method this time, but you may still want to write one. If
you do, please make it a private method – there are other ways to tell whether a Candidate is present in
the election! You may need to get creative 😉
Note that you will also be overriding toString() and equals() here, but in a different way than with
Candidate…
4. The Ballot data type
And now, the brand new part! Each Ballot maintains an ArrayList of Elections, and facilitates a VOTE.
There are two phases to the life of the Ballot class:
1. Adding new Elections to the ArrayList
2. Creating new Ballots
You’ll be setting up your class to enforce that these operations take place in this order! If no Elections
have been added, you cannot create a Ballot; once the first Ballot is successfully created, no more
Elections can be added. This setup for our utility methods would be especially useful for use in a real
world application, where you would want to finalize the elections FIRST and then begin issuing ballots for
those elections.
You’ll accomplish this using a combination of class (static) and instance (non-static) methods and fields.
Each Ballot object will then be able to cast ONE vote in each Election, which your class will facilitate.
More information and a complete list of required methods can be found in the javadocs. Good luck!!
Assignment Submission
Hooray, you’ve finished this CS 300 programming assignment!
Once you’re satisfied with your work, both in terms of adherence to this specification and the academic
conduct and style guide requirements, submit your source code through Gradescope.
For full credit, please submit the following files (source code, not .class files):
● Candidate.java
● Election.java
● Ballot.java
● ElectionManagerTester.java
Additionally, if you used generative AI at any point during your development, you must include
screenshots showing your FULL interaction with the tool(s).
Your score for this assignment will be based on the submission marked “active” prior to the deadline.
You may select which submission to mark active at any time, but by default this will be your most recent
submission.
Students whose final submission (which must pass ALL immediate tests) is made before 5pm on the
Wednesday before the due date will receive an additional 5% bonus toward this assignment.
Submissions made after this time are NOT eligible for this bonus, but you may continue to make
submissions until 10:00PM Central Time on the due date with no penalty.
