As Steve said above, enum identifiers follow the same rules as other Java identifiers. By convention, enum identifiers are typically all uppercase.
But I'm not sure if that's what you're asking.
Note that each Enum instance has an int ordinal that represents the Enum's "position in its enum declaration, where the initial constant is assigned an ordinal of zero." This value is returned by the method ordinal(). For details, see the API documentation for java.lang.Enum.
Additionally, you can add data and behavior to your Enums. See this Enums article for details (note the Planet example about half way through).
"We're kind of on the level of crossword puzzle writers... And no one ever goes to them and gives them an award." ~Joe Strummer sscce.org