Can I get rid of parts of the JRE for my app?

Question

I am trying to figure out how to easily deploy a stand-alone desktop Swing application. It's more like Microsoft Word than the typical Swing business app that deals with networks and databases. I'd like to make this easily downloadable by regular people, like a 10-year old who has installed an IM client, or a 70-year old who has downloaded the latest version of a browser, i.e., just download an installation file and then click to install in the relatively standard manner in which Windows apps are installed.
What I am definitely trying to avoid is making the user go to Sun's Java distribution website, which is written by computer geeks for computer geeks. If a potential user sees that, they'll get confused, give-up, and I'll have lost a potential user.. Since a Swing application that is developed and tested using an earlier version of the JRE won't necessarily work with a later version, I can't make the assumption that as long as the latest JRE is installed on the user machine, everything is fine. As far as I can tell, I need to download a self-contained version of the JRE that I developed with in order to guarantee that the app will run as expected. I also don't want the user to have to download a 15 Mb 1.5 JRE, or the purported 50 Mb 1.6 JRE just to be able to run my little program. (I'm really starting to see why there are no popular Java desktop apps.)
So my question is - if I compile my application down into machine code from binary code, does anyone know if can I get away with running it with a stripped-down JRE? I'm wondering if I can get rid of parts of the JRE that deal with things like interpreting bytecode, networking or database access, none of which I need to worry about. Sun's legal department might not like this, but is this at all technically feasible? I'm actually happy to hear about any ideas regarding shrinking the size of the distribution. Thanks.

Answer 1

I voted for the enhancement request. It is almost exactly what I am concerned with.
I am a big fan of Excelsior Jet. I tried out the free version about a year-and-a-half ago, and was pretty happy with it. It was actually the only machine-code compiler I tried out of several that worked. If I ever get to the point where I can start selling my app, I expect that I'll use it. I've been checking the website every so often since then, and reading about the next version, where a JRE can be included in the distribution. That helped spark my original question. While the worry about making sure my application had the right JRE version will be solved, it still bugs me that I have to ship so much unnecessary JRE code. (I blame Sun for that, not Excelsior Jet.) I was wondering if it was at all technically feasible to strip out the unnecessary code, irrespective of the legal issues. When compiled to byte-code, my program is under 1 MB. When I compiled it to machine code under JDK 1.4, it was about 5 MB. I imagine that compiling to machine-code with the included 1.5 JRE, after compression, will result in a size in the 15-20 MB range. And this after refactoring my program to where it's about 1/3 it's original size. I'm really worried about the direction this is going, and I don't even want to think about what including the 1.6 JRE will require.
Where did you read that I've been programming Java since '97. I was a contractor at Sun between 1995 and 1997, and started working on Java 1.0 apps back then, but I don't ever remember mentioning that. If you asked because you're thinking I should know more about JVM/JRE issues, you're probably right, but I focus almost exclusively on higher-level application and GUI/Graphics issues. The deep-down Java stuff makes me break out into a cold-sweat.