Friday, December 21, 2007

Schema-Typed Languages

BEA Systems may have invented something quite novel and useful. In a recent patent application, BEA's John Schneider proposes using XML schema definitions as data types in, say, ECMAScript. The main intuition is that you would use an import statement to make the interpreter aware of a particular schema definition. From that point on, you could instantiate whole objects based on that schema def, or (if it's a simple data type) declare variables to be of type "MyElement.xsd" and manipulate them directly. Type-checking is delegated to the schema validator; and suddenly you have a scripting language that acts like a strongly typed language and groks XML to boot.

At first blush, it sounds and feels a lot like a new twist on object relational mapping, but it's actually a bit more than that. This goes to the heart of language design and behavior.

Neat. I wonder what BEA plans to do with it next?

Friday, December 14, 2007


I ran across an interesting post by Mary Jo Foley talking about Internet Explorer 8. It mentions that IE8 probably still won't support XHTML properly.

This is all so very wrong.

Wednesday, December 12, 2007

Google Charts

Projects under the heading "Google Apps" don't tend to excite me very much these days, but this one is too good to go unmentioned.

Google Charts is a simple REST-style API for creating graphs and charts on the fly, such as this one:

Details here:

Monday, July 23, 2007

Menus as Non-Modal Dialogs

I was thinking the other day about how best to keep the details of application logic hidden from Swing widgets (in the spirit of Martin Fowler's Presentation Model), the main intuition being that a user app can/should (arguably) be modeled as a set of nonvisual capabilities to which utterly dumb GUI widgets can later be mapped. Achieving this in a clean way is incredibly difficult. (Or at least for me it is.)

I had an epiphany of sorts. When you design a standalone user app (a menu-driven desktop app), what's the first piece of UI you design? The menu system. And what is a menu? In Swing (Java), it's a series of nested buttons. (JMenu and JMenuItem inherit from javax.swing.AbstractButton.)

The menubar never goes away. Some apps let you hide it, in which case it's merely made invisible (it doesn't actually get released from memory). There's a name, of course, for collections of buttons that never go away: a non-modal dialog. My epiphany was/is that a menu system is a collection of non-modal dialogs. (And I hate non-modal dialogs, both as a user and as a programmer.)

In the typical menu-driven app, menus are non-modal dialogs in which each button "knows too much" about deep application internals. The ever-changing state of the entire app is controlled through this collage of interdependent buttons, and managing the underlying ill-formed dependency graph is difficult, and this is why menu apps are a pain the ass to write.

Friday, March 09, 2007

Fractal-Dimensional Transforms

I was on the back porch thinking about image transforms the other morning, and it occurred to me that we just assume that many types of data are either one-dimensional, two-dimensional, or three-dimensional, etc. (with nothing in between), despite the fact that fractals are everywhere in nature. And we apply transformations and convolutions (2-dimensional DCT, in the case of JPEG) to the data without regard for the data's true dimensionality.

So I'm left wondering: how do you do, say, a 2.2D DCT or DFT? What if I want to convolve the fractal residue of a time series?

Wednesday, January 24, 2007

Privacy Leakage Patent

Identity data-mining disturbs me. What disturbs me even more is that you can patent a technique for, say, guessing someone's age based on their purchasing habits (which is what Amazon has succeeded in doing).

Evil, evil, evil.

Thursday, January 11, 2007


It turns out JDK 6 comes with a JavaScript console facility so that you can play with Rhino interactively from a command line. Look for a file called jrunscript.exe in your JDK's /bin directory.

A pretty good article on Java/JavaScript integration in Java 6 can be found on the Sun Developer Network site right here.

Wednesday, January 03, 2007 Dev Hurdles

Over the holidays I decided to wade into the murky waters of OpenOffice development. I was quickly up to my neck in mud.

It turns out I'm not the only one. Key OOo insiders are acutely aware that the barriers to participation in OOo development are way too high (keeping community participation in OOo development way too low).

It's not just that finding all the code is hard or that the C++ codebase is around 7 million lines of code. It's that a full compile-and-build of OOo takes 15 hours on a typical desktop PC. If you can get it to build at all.

Some of the entry-barrier issues are more fully discussed in Jens Heiner Rechtien's 31 Dec 2006 blog.