Com S 362 --- Object-Oriented Analysis and Design

		   EXERCISE: OBJECTS AND CLASSES 2
                 (File $Date: 2003/09/03 05:05:56 $)

The purpose of this exercise is for you to learn some key facts about Java
objects and classes.

As with all exercises, this is to be done individually, not in teams.
And it is due the day this topic is planned to be discussed in class, unless
specified otherwise (see the syllabus at:
http://www.cs.iastate.edu/~cs362/syllabus.shtml). 

As with all exercises, you have two choices for doing the work. You
can either:

  - complete it as specified or
  - write down questions or problems that you had in trying to
    complete it.

If you write down questions or problems you have, these should be
detailed enough so that we can tell that you have read the materials
and thought about them.  (Don't just write: "I couldn't get it to
work; say what you tried and what you didn't understand.)  During the
class where this exercise is discussed, you should try to get help
with these by explaining what you did and what your problems or
confusions are.  Don't be shy; there will be other people with the
same problem, and everyone can learn by discussing these issues.

1. [Object Creation Semantics]

Read sections 1.7.1 and 2.4-2.5 of Ken Arnold, James Gosling, and David
Holmes's book The Java Programming Language Third Edition
(Addison-Wesley, Reading, Mass., 2000).

Explain, using a picture of the run-time stack and the heap, what
happens during the execution of an object creation expression, such as

	new Vehicle(currentSpeed, currentDirection, ownerName)

in Java.

2. [Static vs. Instance in Java]

Read sections 1.7.2, 1.8.3, 2.2.2, and 2.6.1 of Ken Arnold, James
Gosling, and David Holmes's book The Java Programming Language Third
Edition (Addison-Wesley, Reading, Mass., 2000).

(a) Briefly describe the difference between a non-static (instance) field
and a static (class) field.

(a) Briefly describe the difference between a non-static (instance) method
and a static (class) method.

WHAT TO HAND IN

You should have at the beginning of class, written answers to the
above questions (or written out questions and problems you encountered
for each part).  Make sure your name is on these. Attach the
printouts, if any, requested above.

ADDITIONAL READINGS

If you are new to Java you might also want to read the interesting (to
you) parts of the "new to Java" section on-line at

  http://developer.java.sun.com/developer/onlineTraining/new2java/

(If you read that link, I would advise starting with the "step by step
programming" step, which is step 3.)