Outline of Class 53: Wrapup

Miscellaneous

• I'll be gone from 2:30 today until late Monday evening. Sorry about that, but I would like to get my wife back here.
• I'll be in all day on Tuesday, and we'll have a review session Tuesday evening from 7:00-9:00.
• There is an additional electronic course evaluation that you are required to fill out before you can take the final. You will receive a number after filling out the form and must bring that number to the final.
• It appears that the college has moved. Check out http://chronicle.merit.edu/.ads/.ads-by-group/.exec/.presidents/.links.html
• I've finished grading most of your homeworks. There were a lot of common errors, so I'd appreciate it if you'd read the notes (follow the links below). Note that comments on one assignment may also apply to other assignments. I tried to be more lenient on the subsequent assignments because of the delay.
  • Notes on assignment five
  • Notes on assignment six
  • Notes on assignment seven
• Some time next Tuesday I'll get you a summary of all the grades I have for you. Sorry for the delay; William's illness stole the time I had allocated for this.
• We'll spend the last fifteen minutes of today's class filling out evaluation forms (or at least you will).

Exceptions, Revisited

• I saw enough confusion about exceptions on the homeworks that I think we need to talk a little bit more about good program design and error handling.
• A key goal of object-oriented design is the ability to use classes that others design and have those classes work exactly as advertised.
• What happens when something goes wrong? You should throw an exception and let the caller handle the problems.
  • You should not print an error message. It is up to the caller to decide whether or not the error was significant enough.
  • You should not terminate the program. It is up to the caller to do that. Many feel that the only termination should be in your main() routine.
• What do you do if there's an error, and you can't finish the task (e.g., sorting)? You throw the exception, which basically says "sorry, I couldn't do it ... it's up to you to figure out what to do next."

Reflection on Topics Learned

• We've covered a lot of topics in 152 this term. (From talking to my 223 students, it may be more than has been covered before, but that's okay, we needed to cover that much.)
• Here's my quick but incomplete survey
• Algorithms
  • Design
  • Analysis (big O notation, how you determine it, etc.)
  • Common algorithms (sorting, graph algorithms, etc.)
• Data Structures
  • Purpose
  • Information hiding (interface vs. implementation)
  • Common data structures (vector, list, stack, queue, priority queue, heap, tree, graphs, dictionaries)
• Programming
  • Pre- and post-conditions
  • Commenting
  • Debugging and error handling
  • Testing
• Java
  • Basics
  • Error handling with exceptions
  • javadoc
  • Some object-oriented issues
• Fundamental data types
  • Representation
  • Some manipulation
• I've generally been impressed with what you've done, and I'd like to compliment all of you on your good work.

Final statements

• My mother taught Psychology at Boston University for over thirty years. ("Aha, that explains SamR's personality.") She ended every class with the same statement. I try to do the same, although the statement is filtered through my sensibilities.

  Most of us will take or teach other classes. However, this one is unique; none will ever be quite like this it for a number of reasons. The people in the class made it what it was. We should acknoledge each other's contributions and commit ourselves to making similar contributions in future classes. I thank all of you for your contributions.

• Mom also makes a statement on the order of

  While I enjoyed having you in my class, I'm also happy to have you move on to other things. Like any parent, I've enjoyed seeing you grow, but also want you to test your own wings.

• Mom also tells a story of an elementary school teacher she had worked with who was leaving her job. Mom stopped by to give the teacher a goodbye present. The teacher cried. Mom said "I expect that you've been crying all day as you said goodbye to your students." The teacher said "No, I forgot to say goodbye." Since then mom has always made it a point to say goodbye to her classes. I encourage you to say goodbye to your friends and colleagues who you may not see again.