CS203
Spring 2013
Mar 29

• Clone a project from GitHub
• Implement and use iterators
• Use inner classes to implement your iterators
• Test your iterators

1. Configure git for your CS Linux account:
   • Login and enter the following commands at the Linux prompt:

     git config --global user.name "Your Name"  
     git config --global user.email "your@email.com"  
     git config --global color.diff auto  
     git config --global color.status auto  
     git config --global color.branch auto

2. Set up your public sshkey so that you don’t get prompted for a password every time you access your GitHub account:

   ssh-keygen -t rsa -C "your@email.com"

   Note: you will be prompted for what file to save the key in–take the default; you will also be prompted for a passphrase–make one up you can remember

   • point your browser to https://github.com/ and login to your GitHub account
   • in the upper right corner, click on the Account Settings icon (it’s the second icon from the right; hover over it and it should tell you which one it is)
   • along the left hand side of the page, click on SSH Keys, and click the button to add an SSH key
   • in the Title field, type in your Vassar email address
   • from your Linux prompt, cd into your .ssh directory, and type the following command:

     cat id_rsa.pub

   • copy/paste your public SSH key from the terminal into the Key text area of your browser
   • click the Add Key button
   • test if all went well by trying to ssh into GitHub:

     ssh -T git@github.com

     Note: you may be prompted about trusting GitHub’s fingerprint. Reply ‘yes’

   • DO NOT CONTINUE UNLESS THIS LAST COMMAND WAS SUCCESSFUL
3. cd into your cs203 course directory
4. Grab your starter Netbeans project from GitHub using the git clone command:

    git clone git@github.com:Vassar-cs203/lab8.git

5. Open your Lab8 project in Netbeans–it will show up as InnerIterator in Netbeans
   • Note: you may have to fix the reference to the tester library
   • There are two classes in this project: an Examples class for your tests, and a Num class that contains an inner class named PrimesGen
   • Notice that PrimesGen is a private static inner class, defined within Num.
   • Run the project, look at the tests, see if you can figure out what’s going on before you continue...
6. Add a new inner class named NatGen that is also an iterator, but more simply generates 1, 2, 3,...
7. Add a method to class Num named allNats, similar in spirit to allPrimes, but the iterator returned will be an instance of NatGen.
   • Recall that this method is an example of the Factory design pattern.
   • The factory method provides a way to construct an object without invoking a constructor for that object’s class.
   • We need such factory methods when we need to return an Iterator that’s an instance of an inner class.
8. Add a few tests in your Examples class for the allNats iterator
9. Add one more iterator, as an inner class, that generates multiples of 10, e.g., 10, 20, 30,..
10. Similarly add a factory method for your multiples of 10 iterator, and add a few tests.

• When you’ve had enough fun, submit your work using the new submit203 script:
  submit203 lab8 lab8
  • the first lab8 is the assignment name, the second lab8 is the root directory of the project you checked out of GitHub

• Logout and have a good weekend!