Description
Assignment Goals
To be able to share data/code among classes using abstract classes
To use the Java LinkedList class
To become familiar with element-based for loops
Reminders
Please use the default package in your Java project. There will be a penalty for using a named
package.
Starting with this assignment, please include a Javadoc statemnt above each method. There will
be a penalty for forgetting your Javadoc statements.
LinkedList API: https://docs.oracle.com/javase/8/docs/api/java/util/LinkedList.html
(https://docs.oracle.com/javase/8/docs/api/java/util/LinkedList.html)
Note to those with prior Java experience: One goal of 2102 is to help everyone learn when
different iteration constructs (for, while, etc) are needed for a particular problem. Style grading will
check whether you are using appropriate constructs. This week, we will cover the per-element style
for loop, not the for loop that uses a variable to index into elements. For full points, do not use indexbased for loops on this assignment. Use a per-element style loop instead.
We will have covered the material for this assignment during the second week of classes.
Problem Description and Context
For last week’s homework, you developed classes for contestants and matches. Now we want to
build off of those to create tournaments. A tournament is a set of rounds, each of which in turn
consists of a set of matches.
There are two kinds of rounds: initial rounds occur at the beginning of the tournament (like how every
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team plays at least three games in the FIFA World Cup); advanced rounds occur later in the
tournament and involve contestants who advanced from earlier matches in the tournament (such as
the quarterfinals, semi-finals, and finals in the World Cup).
We are going to capture tournaments in Java in a way that reuses the classes and interfaces you
created for homework 1 (you are welcome to update or fix your work from homework 1 as needed).
Programming Problems
1. Starting with your Homework 1 submission, develop an additional set of classes and interfaces
that capture the concepts of rounds and tournaments. In order to let us run tests against your
code, everyone needs to use standard names for interfaces and classes. Use the following:
InitRound , AdvancedRound , and AbsRound for rounds
Tournament for the tournament class
Also create an interface IWinner for reasons that will be explained farther down.
The class constructor signatures should look like the following (parameter names may vary, of
course):
public InitRound(LinkedList
…
}
public AdvancedRound(LinkedList
…
}
public AbsRound(LinkedList
…
}
public Tournament(LinkedList
…
}
2. Both InitRound and AdvancedRound have a LinkedList of matches that contains all of the matches
played in that round. AdvancedRound also has a list of winners from the previous round.
3. Both InitRound and AdvancedRound have a method getMatchWinners() that returns a LinkedList of
all of the contestants that won each match in each round.
4. Both InitRound and AdvancedRound have a method getNumWinners() that returns the number of
winners in the round. Think about how you could use the a call to the getMatchWinners() method
in this method.
5. AdvancedRound has a method isWinner() that takes in an IContestant and returns whether that
contestant was one of the winners from the previous round. This makes sure that there is nobody
advancing who shouldn’t be advancing.
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6. InitRound also has a method isWinner() that takes in an IContestant and determines whether
that contestant is a winner by checking to see that the contestant was a winner in at least one of
the matches that makes up that round.
7. AbsRound is an abstract class that holds fields and method implementations common to both
InitRound and AdvancedRound
8. Tournament has a single LinkedList of all of the rounds (both initial and advanced) that make up
the tournament.
9. Tournament has a method finalWinnerIsValid() that takes in a contestant representing the
tournament winner and checks whether that contestant is a valid winner. A contestant is a valid
winner if he or she has won at least half of the rounds in the tournament. Use the isWinner()
methods in InitRound and AdvancedRound and the IWinner interface to solve this problem.
10. Create a test suite for your work. Put all of your tests and test data in a class
called Examples . Your class must be called this so that the auto-grader can find it!
Just because your program passes all of your JUnit tests does not guarantee that it will
pass all of ours. However, you can minimize the risk that your methods will fail our JUnit tests by
sticking with the proper naming conventions and writing as many edge cases as possible. The
more testing you do, the less the likelihood of failure!
Support Files
Here are a couple of files that may be helpful.
a skeletal Examples.java (https://canvas.wpi.edu/courses/12951/files/1824072
/download?download_frd=1) file showing you the shape of a test case. You should create your own
Examples.java file by right-clicking your project in Eclipse and going to New -> JUnit Test Case.
Make sure JUnit 4 is selected!
a CompileCheck.java (https://canvas.wpi.edu/courses/12951/files/1856638
/download?download_frd=1) file that attempts to create objects from the expected classes and call
the expected methods within those classes. Including this file when you compile will check that
you have the class and method names that our grading tools expect, which saves you from losing
points.
If you get a compilation error involving this file on a class or method that you defined, do not edit
this file. Edit your files instead! As you are working, you may wish to comment out sections of
the file that check methods you haven’t written yet (that’s fine). The final work you turn in should,
however, compile against the entire contents of this file.
Just because your programs compiles does not mean that your program will pass all of the
auto-grader tests! A program can compile but still be full of errors. The CompileCheck file is
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there only to make sure your naming conventions are correct, not that your classes and methods
work correctly.
You are welcome to leave this file in the directory when you submit your work. It can serve as the
main method for your program.
Grading
Homework 2 Grading Rubric (https://canvas.wpi.edu/courses/12951/files/1856637
/download?download_frd=1)
Here are some details on what we will look for in grading this assignment:
Did you create classes with the fields required in the problem?
Do your methods produce the answers expected based on the problem statements?
Is your code neatly indented and presented in a clean, readable manner?
Are your test cases correct relative to the problem statement?
Are your test cases thorough, covering different situations (based on input data) and exercising all
of your code?
Programs must compile in order to receive credit. If you submit a program that doesn’t compile, the
grader will notify you and give you one chance to resubmit within 24 hours; a penalty (25% of the total
points for the assignment) will be applied as a resubmission penalty. Code that is commented out will
not be graded.
What to Turn In
Submit (via InstructAssist (https://ia.wpi.edu/cs2102/) ) a single zip file (not tar, rar, 7zip, etc)
containing all of your .java files that contain your classes, interfaces, and examples for this
assignment. Do not submit the .class files. You may put all of your other classes and interfaces either
into a single file or into separate ones (as you prefer). If you have separate src and test
subdirectories, you may retain that structure in your zip file.
Make sure all of your tests are in separate files from your code, as explained in the Expectations on
Homework page.
