Naming Java Classes and Filenames

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Overview
Class Names
File Names

Java class names use camel case (bumpy) which simply means the first character of each word is capitalized.

Note that spaces are not allowed in any of the names.

Also see alphanumeric

Class Names

Rules

First character -- Uppercase letter or underscore allowed (digit not allowed)
Remaining characters (beyond first) -- Alphanumeric character or underscore allowed (digits allowed)

Examples of Valid Class Names

Rectangle
Rectangle2
RectangleSet

Note: Underscores are allowed but generally not used

Examples of Improper Class Names

2Rectangle
rectangle
Rectangle Set
Rectangle-Set
Rectangle&Set

File Names

Rules:

For a public class, the filename must match the class name
The file extension must be ".java"

Examples:

For the public class Rectangle, the filename would need to be Rectangle.java
For the public class SpaceShip, the filename would need to be SpaceShip.java

Introduction To Objects With Java (Chapter 302 - Classes)

Chapter 302 - Classes Naming Java Classes and Filenames

Chapter Contents Overview Naming Example Coding Compiling Header Body Refs Challenge

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