CSC223 2004F, Class 8: The UML 2: Interfaces

Admin:
* Homework (Friday): Bug World Diagram / Groups of Three
* Homework (Wednesday): Finish Fowler
* Apologies for Friday
* Homework 1 due!
* Office hours switched to 1:30-2:30 (approx) this week.
* Quiz!  "CS223, Quiz 2: YOUR NAME HERE"
  1. What is the name for "<<" and ">>"?  (NOT Shift left, shift right)  Guillemets
  2. What is the notational difference between "<<...>>" and "{...}"?
   * Guillemets indicate *keywords* (what's a keyword?)
     * Part of the programming language?
     * Like a reserved word: The language uses it so you shouldn't.
     * FIXED, RESERVED, MEANING
   * Curly braces indicate *keywords*
   * The difference is too subtle for most of us to understand
  3. What is the notational difference between words surround by <<>> or {} and "plain words" (words surrounded by nothing)?
   * Things that are not keywords should probably not be in angle braces

Overview:
* Why give quizzes?
* Review
* Interfaces

/Why do faculty give quizzes?/

* To gauge whether or not students bothered to do the homework.
* To remind students that they should be prepared for class.
* To assess whether or not students understand the reading/work.
* To enforce attendance.
* It's Monday.
* Tradition.
* Highlight key parts of the reading.

* Didn't bother to prepare class.
* Pure, unadultered, cruelty.
* To give students the opportunity to demonstrate all that they have learned and mastered

/Review/

* The UML is a mostly-graphical language for showing information about object-oriented programs.
* Can notate static and dynamic aspects of programs.
* Basic static notation: The class
  * Three parts: Name, Fields, Methods
    * Some fields are implicit, shown by relationship
* Central static notation: Class relationships
  * Containment (form of association): Solid line, open head
  * Extension/Generalization: Solid line, hollow head
  * Dependency: Dashed line, open head
* When do you ever use a solid head?
  * Communication!

/Introduce Interfaces/

* Show implementation: dashed line, hollow head
* Keyword <<interface>> before name shows that it's an interface
* Show extension of interfaces: solid line, hollow head
  * Given that linear structures contains "add, get, isEmpty", what are stacks and queues but extensions of linear structures that add meaning to those methods?
* What does the ball and socket do?  Show "provide and require interfaces"