That is a good point, but soulbadguy was pointing out that if you make a (non-static) method "final" then you can't override it in a subclass, which should have the same effect, without having to change the semantics by making the method "static".
That said, if there are no actual subclasses of a given class, the JVM will know that, and should be able to inline functions as necessary. That is complicated quite a bit by the fact there is no exhaustive list of which classes are available (the JVM only knows which classes it's seen), and that new classes can be added during the runtime (e.g. Tomcat will load a WAR at startup which will add new classes, or Maven might download a plugin and execute code). But if that _doesn't_ happen, i.e. you load a class and the JVM never sees a subclass and it decides to optimise that part of the code then it will inline what it can (and un-inline it if a subclass shows up later.)
That said, if there are no actual subclasses of a given class, the JVM will know that, and should be able to inline functions as necessary. That is complicated quite a bit by the fact there is no exhaustive list of which classes are available (the JVM only knows which classes it's seen), and that new classes can be added during the runtime (e.g. Tomcat will load a WAR at startup which will add new classes, or Maven might download a plugin and execute code). But if that _doesn't_ happen, i.e. you load a class and the JVM never sees a subclass and it decides to optimise that part of the code then it will inline what it can (and un-inline it if a subclass shows up later.)