If we're really picky (and also if you agree with me that static members are not
OOP), it isn't possible to actually write a fully OOP program in Java. The
"main" method gets in the way.

Leaving that aside, it is possible to avoid the primitives and just use the
objects, although I doubt that many people do.

I don't believe that this makes Java 100% OO, but it does mean that you can use
it in an OO manner. Regardless, of course, it's fairly close.