Challenge

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Prerequisites
Add Instance Variables To Ball Class
Add Instance Variables To Rectangle Class

This is a continuation of the challenge in the previous chapter.

In that challenge we coded up these two classes:

Ball.java
Rectangle.java

We coded up empty class bodies. This will be our starting point for this challenge.

Before getting started, add a new working directory for this challenge.

As always, the challenge follows the full example closely.

Add Instance Variables To Ball Class

Problem Statement:

Review our previous design of the Ball class here...
We want to add an ivar for each property listed in the design
Give the instance variable "r" a data type of "int". Give all other ivars a data type of "String".
Doodle a quick design of the work that needs to be done (optional but just for good practice - any form/style you like)
Copy "Ball.java" from the challenge in the previous chapter (an initial class with empty body) into your working directory.
Code the ivar(s) that were identified in the previous steps
Compile
Fix any compile errors

Hints:

Follow the same steps as in this chapter's "Full Example"
You should end up with two ivars for this class
The class may be simple -- i.e. just the instance variable(s) in the code body similar to the "Full Example"
You do not need to run the class (but you do need to compile it)

Add Instance Variables To Rectangle Class

Problem Statement:

Review our previous design of the Rectangle class here...
We want to add an ivar for each property listed in the design
Give both instance variables a data type of "int"
Doodle a quick design of the work that needs to be done (optional but just for good practice - any form/style you like)
Copy "Rectangle.java" from the challenge in the previous chapter (an initial class with empty body) into your working directory.
Code the ivar(s) that were identified in the previous steps
Compile
Fix any compile errors

Hints:

Follow the same steps as in this chapter's "Full Example"
You should end up with two ivars for this class
The class may be simple -- i.e. just the instance variable(s) in the code body similar to the "Full Example"
You do not need to run the class (but you do need to compile it)

Introduction To Objects With Java (Chapter 303 - Object Data)

Chapter 303 - Object Data Challenge

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