Overview

For this assignment, you will implement the class described by the UML diagram below. Also, you are responsible for designing and implementing a test program that ensures that your Fraction class is implemented correctly.

Assignment

Implement the Fraction class shown in the UML class diagram below.

Be sure to note the following:

• The default constructor which should create an object with the value 0/1.
• The second constructor should create an object with the value passed in as the numerator and a denominator of 1.
• The third constructor should create an object with the first value passed in as the numerator and the second value passed in as the denominator.
• Optional: The string passed to the fourth constructor should be of the form -9/20 or -9 / 20. If the string is not of this format, an error message should be displayed, and the object should be given a value of 0/1.
• add should return a reference to a Fraction object that is the sum of the object upon which the method was called and the object passed in.
• subtract should return a reference to a Fraction object that is the object upon which the method was called less the object passed in.
• Optional: divide should return a reference to a Fraction object that is the object upon which the method was called divided by the object passed in.
• multiply should return a reference to a Fraction object that is the product of the object upon which the method was called and the object passed in.
• In the above four methods, the value of the object upon which the method was called and object passed in should not be modified.
• equals should return true if the object upon which the method was called and the object passed in represent the same value. Otherwise, the method should return false.
• Optional: compareTo should return 0 if the object upon which the method was called and the object passed in represent the same value. If the object upon which the method was called represents a smaller value than the object passed in, -1 should be returned. Otherwise, 1 should be returned.
• toString should return a string that displays the value of the fraction. The format of the string should be in one of two forms: -1/4 (not 1/-4) or 0.25. (see displayAsDecimal for more details).
• displayAsDecimal determines the format of the string returned by toString. If the method was most recently called with true being passed to it, the format of the string returned by the toString method should be of a decimal form (0.25). Otherwise, the string returned by the toString method should be in fractional form.
• The denominator of a Fraction object must never be zero. If the user attempts this (e.g., using a constructor, dividing by zero, etc), an error message should be displayed, and the object should be given the value 0/1.

Test Program

You should also write a test program that ensures that your implementation of the Fraction class is correct. This program is for your benefit. It will not be graded.

Submission (due at 11pm the day after week 7 lab)

Each student must submit their class with complete functionality. In addition, each the class and each method should be documented using the javadoc format discussed in lecture and a comment at the beginning of the file must include: Course name, Quarter, Assignment name, Author's name, and date (see here). Student's must use the electronic submission form to submit their code.

Enter your MSOE username for the username, select "Lab 6" for the assignment, select your Fraction.java implementation for the report file name and leave the support file name blank.

Acknowledgment

This laboratory assignment was developed by Dr. Chris Taylor.