Question

I’m coming from c#, and find java’s switch statement a bit confusing.

You can only switch on a character, yet you can switch on an enumeration.

Is this because it switches internally on the value?

Why would you want to add methods to an enumeration?

Answer 1

It sounds like the assumption behind your question is false. You can switch on enum values, integer types (char, int, byte, etc.), or String instances.

Internally, all switches compile to one of two instructions, lookupswitch or tableswitch. Both instructions require that each case be labeled with a distinct integer. When you use an enum value, the “ordinal” of the value is used. When using String instances, the compiler inserts additional code to map each string to a unique value. Other types are used directly. You can read more about this in another answer.

Methods on an enum serve the same purpose as methods on any other object. You can use them to implement polymorphic behavior, or as simple accessors, or whatever.