CSC152 2004F, Class 3: An Introduction to Java

Admin:
* Quiz: What is the definition of OOP you found and how does it relate to what I said in class?  Make sure to give me the URL you found.  mail to <rebelsky@grinnell.edu>
* EBoards
* Change in standard way of teaching Java.
* Handouts forthcoming.
* Homework: Extend today's example in any way you see fit.

Overview:
* Your first Java program.
* Configuring the MathLAN for Java.
* Your first Java program, revisited.
* Adding input (if there's time)

Your first Java program:
* Begin with package SOMENAME
  * Packages group related objects/classes together
* Followed by "public class SOMENAME"
  * Class names begin with capital letters and are mixed case
* (See sample code)
* Two steps to running Java programs:
  * (1) Compile the .java files with "jc FILENAME.java"
  * (2) Run the main method in some compiled file with
  	"ji PACKAGE.FILENAME"
* Some morals from writing the code:
  * You name objects with
  	TYPEOFOBJECT NAMEOFOBJECT
	(let ((foo ...)))
    * Java requires you to *type* every object (say what role it plays)
  * You usually create new objects with
       = new TYPEOFOBJECT(SOMEPARAMS)
  * Once you've created an object, you tell it to do something
     NAMEOFOBJECT.METHODNAME(PARAMS)
* How will you learn what kinds of objects you can create and what methods they have?
  * Reading and reference
  * Experience (e.g., you remembmer string-ref, string-append, string<=?)
  * You will soon design your own objects (which you should then know about)