The Cliffs of Inanity

Sat, 01 May 2004

Free Java, Again

There's more noise from Gosling about open-sourcing Java. You can also read about it on sys-con.com and, of course, SlashDot.

Gosling usually dissembles a little when talking on this subject, and some things are usually unclear, so I'm going to go point by point. Also on SlashDot we see the usual misperceptions, but since they are very common in the Java development community I'll take them on as well.

Why does IBM send open letters?

I don't know why they send them. Gosling's claim is that this is "kindergarten-ish", but we don't really know that IBM hasn't already tried direct talks with no resolution. Also take a look at IBM's comments on most of the JSRs they participate in...

One might also reasonably ask: why doesn't IBM just write a free Java themselves? They already have a lot of the parts: two excellent compilers (jikes and the one in Eclipse), the JikesRVM virtual machine, contributions to Classpath, ICU, plus lots of other bits they hold more closely (the J9 VM). The answer to this question can only be that they've signed something with Sun preventing them from doing so. The reality is that IBM could easily write the missing parts of Classpath, if it liked.

BTW, for those following along, I never did get a reply from Bob Sutor. I'm not really surprised, but it is a bit disappointing.

Doesn't IBM already have the source?

Gosling is at his most deceptive here: "Which means that about the only thing that they could get from liberalization is to be able to skip testing." To hear him say it, the JVM licensing is just like open source, except for a testing requirement. If only this were true. The truth is, the TCK costs money. It has never been available to any free software implementation under an acceptable license.

As I've said many times before: it would be great if Sun opened their implementation. That would be really wonderful (even though it would probably kill literally years of my work :-). However, it isn't strictly needed. Instead we really just need three things to make a Free Java:

• Access to the TCK on acceptable terms
• Involvement in the JCP without contamination or other unacceptable constraints
• Easing of the requirements on subsetting

Hasn't IBM helped with Java already?

Well, sure they have. Gosling makes a big deal out of the Swing/SWT thing, but I see that as just a technical dispute, not a major political one. It's a mistake to assume any company like IBM acts with a single mind; I'm sure even in the Eclipse project there are dissenting voices. For instance, the VEP plugin works with Swing. And, as for IBM championing Swing and then going with SWT, which looks more AWT-ish (but isn't), well, we all make mistakes. So what?

In the bigger picture, I don't care why IBM wants Java to be free software. Their motivations are their own. Mine are the same ones that have been my passion for nearly 14 years now: the ability to fix bugs that affect me, to add features I think are needed, to work on projects in cooperation with like-minded comrades, to avoid being locked in to any one company's view of the world. Personally I find APIs wonderful, but even good documentation is no substitute for an occasional (contamination-free) look underneath the hood.

If you look around at the commercialization of free software, one thing you'll see is that different companies come along and try to own some critical piece of infrastructure. They want to impose a private tax on free software, setting themselves up in a privileged position. To my mind this is antithetical to the goals of the movement as a whole. The point is to avoid these taxes -- the infrastructure must be free. We have to fight these wherever we find them; unfortunately a fair part of the free Java world has fallen for Sun's bait.

Will IBM open DB2 and WebSphere?

Gosling throws this in, in an attempt to change the subject. We aren't talking about DB2 or WebSphere, we're talking about Java. For all we know, IBM doesn't even own all the IP in these and couldn't free them if it wanted to. Heck, companies have lost the source to their programs before, maybe that happened and they're just too embarrassed :-)

Developers are afraid that Java will fork

This is one of the big ones, the real reasons that we can't blow off and that aren't mere spy-vs-spy stuff.

What does it mean to fork Java? Or to fork anything? I know this sounds metaphysical and sort of stupid, but I'm serious. Suppose we all take the Java source and just go crazy, adding features, removing APIs, all those bad things. Well, Sun -- or, hopefully, some more neutral entity like a nonprofit set up for that purpose -- will still control the branding. Remember the flap about "gcc 2.96"? I still hear about that from time to time (and I don't recall ever once hearing anything nice). That was all a branding problem, not a forking problem per se. There's a strong sentiment in the community that the upstream project controls the brand, and you violate this at your peril.

Second, the truth is, Java has already suffered most of the bad effects of a fork. While Sun has in general done an excellent job of keeping Java compatible, there are still places where it is not. There is valid bytecode that will verify in some releases but not others. All releases have bugs of various flavors. There are APIs that never quite worked, or that are underspecified. There are even a couple cases where Sun has violated binary compatibility by changing constants or interfaces. Java programmers already have to pick specific target versions and test on multiple platforms.

(Don't get me wrong. In this area Java's promises are, generally, on target. When developing libgcj, we've noticed that most pure Java changes are much simpler than changing target library code in other languages, simply because the portability story is so much simpler. You just don't have to do as much work, and the idea of an autoconf-like tool for Java is delightfully absurd.)

Third, another truth in the free world is that the upstream projects usually have significant control, and the Linux vendors generally have a strong commitment to compatibility. Sure, you do get some horse-race effects where one vendor or another will try to put out a release with some feature or kernel version earlier than anybody else. However, this isn't a problem -- this is a strength! For instance, if Red Hat puts out NPTL, or SELinux, or whatever, this gives the community a platform on which to test and modify their applications in advance of general acceptance. And if a feature turns out to be a bad idea, it just disappears.

For something like Java, everybody already recognizes that one of its strengths is its cross-platform API compatibility. It would be dumb to hurt that, sort of like adding a gratuitously incompatible change to Perl or Python. Why would anyone do that? The whole point of shipping the thing is to enable your customers to run the code they already have, or code that they get elsewhere off the net.

So, I think an open Java would in fact not fork in any significantly harmful way. I expect we would see some minor implementation divergences, perhaps process ports of different quality across distributions, different default UI themes, etc. That is, mostly trivia, and the non-trivial would be merged upstream gracefully (assuming upstream is in fact a graceful place with which to merge -- process matters).

Maybe Sun is worried about malicious entities out there, i.e., Microsoft. That's sort of an absurd worry at this point, seeing that MS now has .NET. (Sun could have plenty of other worries too; they don't share them with me :-)

Patents

To my mind, the various tos and fros about Java are not very important. It is a bit entertaining to see Sun put out Open Source feelers occasionally, then watch everyone get riled up over nothing. Whee! The various Free Java efforts will get there eventually -- it might not seem like it right now, but that's how free software works. It never seems real until suddenly it is better than what you're selling.

The real danger we're facing comes from patents. Microsoft, IBM, and seemingly everybody else is patenting things as fast as possible. This is a huge hole for our community, and I'm really concerned that in a few years we'll be left unable to ship anything meaningful. It seems that most new technologies come with a raft of bad patents attached.

The solution? I think we need a Free Patent Foundation, that helps free software developers file patents, and then uses them for the benefit of the whole community. The goal would be to get a broad enough range of patents that we could force cross-licensing with everybody, sort of eliminating patents as a relevant force.

That's the dream anyway. I have no clue how to set this up.

posted at: 18:25 | path: /software | permanent link to this entry