Its late stage capitalism at its very finest
There is a school of thought that suggests that as capitalism matures it becomes 'rentier' in nature -- that it, it ceases to produce anything useful but relies on extracting ongoing payments -- rent -- for its income stream. There's a lot of historical precedent for this observation although I'd say its not necessarily the system that breeds this mindset, its part of the evolution of corporations.** Anyway, trying to squeeze rent out of owning piece of so-called intellectual property is the modern way to make money so what Oracle's doing is just its business model, it fits in with its attempt to own Linux and whatever else it gets its hands on. We need to push back against this mindset because it does lead to stagnation and decay, we've all seen and experienced innumerable examples of how destructive this is to industry. Its not as if Java is a particularly novel concept as languages go, its just a particular implementation of a Pascal like language that had strict licensing conditions specifically to prevent it fragmenting and so screwing up its 'write once, run anywhere' purpose. The licensing wasn't designed so that a monopolist could lay claim to it and then try to squeeze everyone (after the fact, of course -- you never do this up front because you need to get the base established).
To me, trying to patent a computer language or assert copyright over it is like trying to patent English.
(**I've always thought that corporations would love to adopt the business model of he the IRS or HMRC -- taxation is the best business to be in because its relatively small overhead for the revenue stream collected and no messy products to make, warehouse or ship. Its not such a fanciful notion, either -- selling of taxation powers was historically a way for kings to raise sums of money. (...and some of the outsourced government functions in the UK seem really close to being a modern version of this practice.))