Prelim 3 Topics

All Earlier Topics (review questions, exams, projects, exercises, section, etc.)
- emphasis is on new topics but you are responsible for all earlier topics, e.g.
  nested loops, random numbers, search

Classes and Objects and Methods
- references, $null$, $this$
- $final$
- designing
- Box Scope Diagrams: everything to date, e.g. arrays and methods and $static$
+ Methods
  - writing, calling, returning values, return types
  - formal parameters, actual parameters, pass by value
  - overloading
+ Constructors
  - are indeed methods
  - designing, calling
  - default constructor
- Class/$static$ versus instance/non-$static$ (variables and methods)
- default values for instance variables
+ Encapsulation
  - $public$, $private$
  - why is $main$ $public static void$?

Strings and Characters
- Strings are objects
- ASCII text, UNICODE, text files
- TokenReader to read in files (we would give you the template)
- String methods: length, toCharArray, indexOf, toLowerCase, new String, charAt
- casting $char$ to/from $int$, e.g. converting case

Arrays
- aliasing
- arrays are objects
- elements of arrays are instance variables numbered 0...
- $length$ variable
- default values
- how to declare and create arrays
- initializer lists and anonymous arrays
- searching for a value in array (linear search)
- arrays of objects (array_objects0.java)
- 1-D arrays
+ Arrays of Arrays
  - row major (column major will not be on Prelim 3)
  - ragged arrays
  - 2-D arrays
  - terminology: matrix, table, 2-D array, array of arrays

Project 4 (recap of some topics seen on Prelim 2)
- objects and methods
- $null$
- linear search through object references

Project 5
- equations of motion (e.g., position += velocity*dt)
- know how to test for (non-)overlapping rectangles
- graphics (use commands we provide for you, like $fillOval$)
- hint: see solution to bonus work!

Project 6
- terminology!
- substitution ciphers
- using/making encryption and decryption keys
- see "Strings and Characters" and "Arrays" above
- $static$
- printing arrays
- distance between matrices