Overview

• Preliminaries.
  • Admin.
  • Upcoming Work.
  • Extra Credit.
  • Questions.
• Questions/notes on anonymous functions.
• Quick notes on anonymous inner classes.
• Lab.

Preliminaries

Admin

• New lab partners. (These will last through Tuesday. We'll get new partners Wendesday for GHC.)
• Office hours
  • Today 2:15-3:15
  • Next week back to normal (MThF 1:45-3:15; walking 1:15-1:45) plus 8:00-9:45 most days.
• Mira is running a review session Sunday night!
• I forgot to talk to RHB Wednesday about the "no exception" problem.
• GHC folks: Please bring me GitHub stickers (as many different ones as you can).
• Folks have asked me to summarize each reading. Note that the daily outlines often contain a summary of the key points from the corresponding reading. (The summary is in a different form, since they are my notes of what I'd hope to talk about.)
• Apologies about the Predicate class in today's lab. I wrote the lab before Java included its own such class and have not yet had a chance to update the code.
• It's Friday. I hope you have a chance to relax and recover this weekend. As always, please think in advance about what is right for you. If you choose to partake, please do so in moderation. If you do activities with other people, please make sure that they have decided that the activity is right for them.

Upcoming Work

• HW 7 assigned.
  • Refer to Wednesday's eboard for details.
• Exam 1 distributed next Wednesday. (GHC folks should look online.)
• Readings for Monday.
  • Algorithm Analysis (to be released Saturday night)

Extra Credit Opportunities

Academic

• CS table TODAY: Serendipity and Computing (with Grinnell's Artist in Residence)
• Grinnell Prize Events next week.

Peer Support

• Neverland Friday at 7, Saturday at 2 and 7, Sunday at 2
• Ajuna's Radio show Mondays at 8pm. Listen to African music
• Ezra's Radio show Thursdays at midnight. Radio melodrama.

Miscellaneous

Questions

• Homework back a week from Monday (we hope).

Quick Notes on Anonymous Functions

• Syntax is confusing.
  • When you define the interface, if it has only one undefined function and you tag the interface with @FunctionalInterface, you can use lambdas whenever you want to build an object in that interface. (You don't have to, but you can.)
• Why bother writing the lambdas?
  • Much less coding.

• How do I write that generic method?

  public static <T> void printSelected(PrintWriter pen,
      Vector<T> vec, Predicate<? super T> pred)
  

Quick Notes on Anonymous Inner Classes

• A way to build objects (with new methods and fields) without having to name them and type lots of extra text.

• General forms

  new INTERFACE()
    {
      void method1() { ...}
      void method2() { ... }
    };
  
  
  new CLASS()
    {
      void additionalMethod() { ... }
      @Override
      void override() { ... };
    }
  

• Example with predicates

  Predicate even = new Predicate() { public boolean test(Integer i) { return (i % 2) == 0; } // test }; // new Predicate

Lab

Sam needs to rewrite the lab to use something that sounds more GUI oriented (e.g., Greetable -> ButtonMaker; Greeter -> Button; greet -> click).