Chapter 13
Programming with Objects and Classes
IN THIS CHAPTER
Programming with class (and with style and finesse)
Making objects from classes
Joining the exclusive “I understand classes and objects” society
Chapters 7 and 8 introduce Java’s primitive types — things like int, double, char, and boolean. That's great, but how often does a real-world problem deal exclusively with such simple values? Consider an exchange between a merchant and a customer. The customer makes a purchase, which can involve item names, model numbers, credit card info, sales tax rates, and lots of other stuff. A purchase is more complicated than an int value. It's more complicated than a double value. How do you represent an entire purchase in a Java program?
In older computer programming languages, you treat an entire purchase like a big pile of unbundled laundry. Imagine a mound of socks, shirts, and other items of clothing. You have no basket, so you grab as much as you can handle. As you walk to the washer, you drop a few things — a sock here and a washcloth there. This is like the older way of storing the values in a purchase. In older languages, there's no purchase. There are only double values, ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access