CO[R]RECT: [R]ange

When you use Java’s built-in types for variables, you often get far more capacity than you need. If you represent a person’s age using an int, you’d be safe for at least a couple million more centuries. Inevitably, things will go wrong, and you’ll end up with a person a few times older than Methuselah, or a backward time traveler—someone with a negative age.

Excessive use of primitive datatypes is a code smell known as primitive obsession. A benefit of an object-oriented language like Java is that it lets you define your own custom abstractions in the form of classes.

A circle has only 360 degrees. Rather than store the direction of travel as a native type, create a class named Bearing that encapsulates the direction along ...

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