Instructions for DNA lab

Background

You will be implementing a simple simulator for DNA splicing, using the test-first software engineering methodology. Don’t worry about the scientific details of DNA splicing. For us, a strand of DNA is modeled by a Java String consisting of the characters C,G,T, and A (repeated any number of times in any order). When implementing the splicing methods in the interface IDnaStrand, read the JavaDoc carefully, and implement the method to the best of your ability, but you can just ignore any details that you find confusing. The real point of this lab is the test-first methodology, not the science of DNA splicing.

Instructions

  1. Create a new Java project in Eclipse (or use another IDE if desired, but the instructions below assume Eclipse). Make sure to add JUnit as a library for this project. Any version of JUnit should be fine.
  2. Import the file IDnaStrand.java into the project.
  3. Create a new class, called SimpleStrand, which implements the interface IDnaStrand. If you use the features of Eclipse correctly to do this, Eclipse will automatically create stubs of all the methods that need to be implemented.
  4. Remember, the whole point of this lab is to write the tests first. Do not edit the stubs of the methods in SimpleStrand!
  5. Create a new JUnit Test Case (search around for this option under File|New). Make sure to specify SimpleStrand as the class being tested. Your test class can be given any reasonable name, such as SimpleStrandTest.
  6. Now for the interesting part. Write one or more tests! Easy challenge: which method(s) need to be tested first? These are the tests you will need to write first.
  7. Implement the method(s) for which you have written test(s).
  8. Continue with this pattern: write one or more tests, then implement the corresponding methods. Do not edit any method in SimpleStrand until you have written a comprehensive test for it.

Acknowledgment: IDnaStrand.java is taken from the Stanford Nifty Assignments repository, and this lab appears to have been originally authored by Richard E. Pattis of UC Irvine. However, the file is used for a completely different purpose here. If you’re interested, you can see the full context for this file in Duke University’s DNA splicing lab.