Question

I’ve got java enums all over the place, and while I’ve seen various good ways of selecting ones at random, it feels like there should be a way to do this generically; that is, one method for selecting a random value from any supplied enum. Say,

public static <E> E randomMember(Enum<E> enumeration){
...
}

Yet I can’t figure out a way to do it, and the lack of Google results leads me to believe it isn’t possible (or isn’t a popular request, I guess).

Any thoughts?

Answer 1

You should be passing enum‘s class, not enum‘s instance to get this to work:

public static <T extends Enum<T>> T randomMember(Class<T> enumType) {
    T[] constants = enumType.getEnumConstants();
    // Return a random element of constants array
}

...

MyEnum rand = randomMember(MyEnum.class);