@MustOverride annotation?

Question

In .NET, one can specify a \"mustoverride\" attribute to a method in a particular superclass to ensure that subclasses override that particular method. I was wondering whether

Answer 1

... and if declaring a base class abstract is not an option you can always throw an UnsupportedOperationException

class BaseClass {
    void mustOverride() {
        throw new UnsupportedOperationException("Must implement");
    }
}

But this is not a compile-time check of course...