Stopping inheritance without using final

Question

Is there any other method of stopping inheritance of a class apart from declaring it as final or by declaring its constructor as private?

Answer 1

Two more options:

• make each method final, so people can't override them. You avoid accidental calling of methods from subclass this way. This doesn't stop subclassing though.

• put check into constructor for class:

  if (this.getClass() != MyClass.class) {
      throw new RuntimeException("Subclasses not allowed");
  }
  

  Then nobody will be able to instantiate subclass of your class.

(Not that I suggest using these techniques, it just came to my mind. I would use final class and/or private constructor)