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Trail: Learning the Java Language
Lesson: Classes and Inheritance

Questions and Exercises: Creating Classes

Questions

1. Consider the following class:
public class IdentifyMyParts {
    public static int x = 7; 
    public int y = 3; 
}
a. How many class variables does the IdentifyMyParts class contain? What are their names?

b. How many instance variables does the IdentifyMyParts class contain? What are their names?

c. What is the output from the following code:

IdentifyMyParts a = new IdentifyMyParts();
IdentifyMyParts b = new IdentifyMyParts();
a.y = 5;
b.y = 6;
a.x = 1;
b.x = 2;
System.out.println("a.y = " + a.y);
System.out.println("b.y = " + b.y);
System.out.println("a.x = " + a.x);
System.out.println("b.x = " + b.x);

Exercises

1. Write a class whose instances represent a playing card from a deck of cards.

2. Write a class whose instances represents a deck of cards.

3. Write a small program to test your deck and card classes. The program can be as simple as creating a deck of cards and displaying its cards.

Check your answers. (in the Learning the Java Language trail)
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