CS494, Spring 2005
Homework 1 (version 2)

This assignment is based on a tutorial and exercise from NCSU. Original link is here.

You may work in pairs or alone on this assignment.
Due date: Turn in files on Friday, Feb. 18, by 3pm.

For this exercise we will be using the CoffeeMaker project developed at NCSU. Download the CoffeeMaker project from here. Unzip the CoffeeMaker project to your Eclipse workspace directory, then choose the Import command from the File menu. This should create a new project in your Workspace. (Note: the path to the junit.tar library is probably wrong. You may need to make this point to the junit.tar in your Eclipse plugins folder.)

We all know that most computer scientists love caffeine, so the Computer Science department is looking to put a coffee kiosk in the new building. The coffee kiosk must be able to make coffee for students to purchase. A full set of User Stories can be found here. User stories are a requirements technique commonly used in Extreme Programming; if you have questions about what these mean, contact the instructor or TA.

The CoffeeMaker code is complete; however, we need you to create and run acceptance tests on the last three functions of the CoffeeMaker. These functions are: 1) Delete Inventory, 2) Check Inventory, and 3) Purchase Coffee. [We're not doing acceptance testing with the tool NCSU is using, so there is nothing for you to do with these functions.]

What we want you to do with this code:

• There are currently 5 (very obvious) bugs in the system. We need you to generate unit tests or improve existing unit tests to find at least 3 of these 5 bugs. Write down what you find a list that briefly describes the bug and where it is. You can improve your scores by finding more than 3 bugs.
• After finding the bugs and creating unit tests that reveal them, create a 2nd version of your system and fix the bugs. . You will need to show that your unit tests pass. (Note that you will now have two versions of the system -- one showing failing unit tests, and the other with bug fixes that passes the unit tests.)
• Other than these errors in the code, identify at least two other bad or questionable Java coding issues in this system. These might include: violations of the DRY directive (don't repeat yourself AKA "Write Once"); use of collections; poor class design; poor use of references; etc. Suggest improvements.

Deliverables:

• A Word, HTML, or text file that contains info labled "document" below.
• In the document, have the list of bug descriptions found in the CoffeeMaker.
  • Grading: 30% possible. For 3 errors found, maximum of 20% for this. For the 4th and 5th, an extra 5%.
• Create two Eclipse projects: one that has buggy code that fails the unit tests, and the other has corrected code that passes the same unit tests.
  • You will demo to the Instructor or TA how both systems run with JUnit in Eclipse.
  • Also, zip or tar these so they can be opened on a Windows machine, please.
  • Grading: 40% for demo and the quality of JUnit tests.
• In the document, note if any of the techniques, e.g. Right-BICEP, applied to the tests that found the bugs, or discuss what you did in the unit tests to find these.
  • Grading: 5%
• In the document, list Java coding issues found in the system.
  • Grading: 25% possible. Max of 22% for discovery, descripton and improvement for just two problems. More problems can get you the full 25%.

  What and how to submit: Using the ITC Toolkit (from link on the class home page), submit the document file and also the Zip file(s) separately.
  Demonstration: We'll announce how you'll do demonstrations shortly!