Introducing enumerations
An enumeration is a list of all the possible values in a logical collection. The Java enum is a great way of, well, enumerating things. For example, if our game uses variables that can only be within a specific range of values, and if those values could logically form a collection or a set, then enumerations would probably be appropriate to use. They will make your code clearer and less error-prone.
To declare an enumeration in Java we use the keyword, enum, followed by the name of the enumeration, followed by the values the enumeration can have, enclosed in a pair of curly braces {...}.
As an example, examine this enumeration declaration. Note that it is a convention to declare the values from the enumeration in all-uppercase characters:
private enum zombieTypes {
REGULAR, RUNNER, CRAWLER, SPITTER, BLOATER, SNEAKER
};
Note at this point we have not declared any instances of zombieTypes, just the type itself. If that sounds odd, think about it...