MySQL has been losing mindshare among *nix geeks to sqlite and other similar programs lately. Bluntly, I'm not that optimistic about the future of their product, and I'm not that worried about it. You will find that -- not a majority but a large number of bloggers and commentators on tech websites are saying the same thing. It's probably doomed but don't blame Larry Ellison.
Blaming Larry Ellison is fun though. I mean there was his priceless remarks before he brought out a rebranded RHEL as "Unbreakable Linux". The man doesn't get Open Source. I don't think he's out to get anyone in the Open Source Community but -- he made his fortune with a company which used technology IBM developed and made freely available, and he really hasn't been generous himself, while Red Hat has also taken a lot of freely available technology and shown you can be very generous and still make a lot of money.
Java I am exactly optimistic about. I don't know if you have worked with gjl -- the GCC front-end which compiles java programs not into jar files but into executables. Jobs when he was at NeXT computers got into some sort of nastiness with the Free Software Foundation developers over an Objective C frontend for GCC. Now he's back at Apple he's using that frontend. GJL got started among some hard feelings about Sun's licensing of Java, which only recently went Open Source. In any meaningful sense. Now Java is even being distributed by Debian (known for their ABSOLUTE insistence on REAL OPEN SOURCE LICENSES -- take that Mozilla Foundation) GJL has not entirely faded away but may very well make a comeback because the licenses Ellison can claim are probably limited. What he will do with Java remains to be seen. If he can monetize it more power to him. If he can't, GJL will grow.
OpenOffice is a funny thing to worry about for a couple of reasons. One is StarOffice, which, even with OpenOffice out is worth the money -- if you are on Windows which I am not. You don't use it though. That's what you said. The other is AbiWord, which has a smaller memory footprint and handles doc files better (even OpenOffice doesn't handle docx files). For spreadsheets Gnumeric is a very good choice and we've already mentioned databases. The bottom line is that Office doesn't just provide excess functionality it provides UNNECESSARY excess functionality. So to some extent does OpenOffice. You can be more efficient with fewer of its features. Of all the products Ellison has acquired, that one seems like the one he can monetize most easily. I wouldn't worry about it.
The two things which one might worry most about are the things you haven't mentioned: the hardware, which gives Ellison the ability to compete with IBM and OpenSolaris. But then again, most people don't think about that much. An acquaintance who works for Cisco described it as a large memory footprint and no compiler -- who needs another Vista? The reality is it was created for minicomputers, and most thinking these days uses microcomputers -- alone or in networks -- as a base.
Your job and your code are probably safe because of GCC. What is GCC? A cross-platform compiler. Not just a compiler but one which can compile the same code across several operating systems and chipsets. Java technology has been working with it for a while, and should continue to, whatever happens.