February 2003 Archives

HP has a paper (PDF) reviewing various orchestration technologies, tools and standards.

Web services technologies are beginning to emerge as a defacto standard for integrating disparate applications and systems using open, XML-based standards. In addition to building web services interfaces to existing applications, there must also be a standard approach to connecting these web services together to form more meaningful business processes. In 2002, a number of new standards were introduced to address this problem, including BPEL4WS and WSCI. The purpose of this paper is to provide a review of these emerging standards, to help the reader better understand how web services orchestration can be accomplished today.

Ted Neward took a few minutes to play with and blog about drools. Thanks, Ted!

The Werken Company also maintains a couple of other open-source projects, including one that caught his eye--and mine, when he mentioned it to me--called drools, a rule-based inference engine, much as tools like ILog Rules and Jess are. (Two others I hadn't heard of before but are mentioned in the drools documentation are Haley Eclipse and CLIPS.) Naturally, having been interested in Jess long before this and having consulted for a company that was deeply involved in the whole business rules concept, I had to take a look. After about ten minutes' worth of looking and experimentation, I figured I'd blog about it. :-)

As it sometimes goes, our involvement in our latest contract project has come to an end. The Werken Company now has excess capacity to help you and your project. We can staff from one to a half-dozen engineers (not staff programmers) on your projects needing hard-core gearheads.

So, if you have a need, please send questions, RFPs or good jokes to bob@werken.com.

USF CS652: Programming Languages is a course taught by Terence Parr the man behind ANTLR and jguru.

Because programming languages are at the core of writing software, programmers should have a thorough understanding of how languages are designed, implemented, and manipulated. This course concerns itself specifically with the implementation and translation of computer languages, leaving an in-depth study of language design to another course. Students will learn the formalisms behind computer languages, but the focus will be on developing the ability to build languages and their translators.

This class is only moderately difficult for the most part, though some of the language formalisms take a while to sink in. Well, actually you have one major hurdle to get over and then it's easy--abstraction in the sense of recursion, meta-language, programs that generate other programs (or even themselves), etc... If you get a headache when you try to figure out how the first C compiler could have been written in C, you might invest in a big bottle of aspirin

Ter is making lecture notes and lecture audio available for download.

I don't typically follow the meme bandwagon, but time-management is something important to me. I forget where I picked it up (maybe Getting Things Done), but there are ostensibly two axes that can define any activity: important and urgent. Not all things are important, but they may be urgent, if they are to be done at all. Not all things are urgent, but it may be important to get them done.

For example, filing taxes is quite important, but not necessarily urget just yet. Getting the trashcans to the street today since it's trashday is urgent, but not overly important, since we have very little garbage this week.

I think the key to managing time effectively is finding the things that are both urgent and important and doing those. Defer the items that aren't urgent and important. I find I have the most mental stability when I accomplish things in the following priority order:

1. Urgent and important
2. Important
3. Urgent
4. Luxury

Okay, time to jump off the bandwagon now. I've said my piece.

public-ws-chor@w3.org from January 2003: Re: Yet Another Choreo is an interesting message from the W3C group discussing the WS-Choreography recommendation. They mention petri nets and Aalst and attempt to view themselves in the context of BPML and BPEL4WS.

Now, I typically don't think too much of many of the W3C's recommendations, but this thread shows me there's some smart peoplle really considering the issues here.

Now, if only it wouldn't cost me $50,000 to join the W3C...

Thanks to James Strachan for pointing this thread out to me.

I would definitely urge the WS Choreography WG to look at models that combine PetriNet with process algebra and pursue the development of a specification along these lines.

Today, the 9th of February, is my lovely wife's birthday.

Happy birthday, Rebecca!

The werkflow website has been slightlyt updated to point to the current code and javadocs.

For anyone playing along at home, the appropriate CVS repository to check out used to be wfx but now it is simply werkflow.

To clarify some ideas floating around out there the the blogburgh....

werkflow no longer uses drools but instead uses a purpose-designed implementation of a RETE-like algorithm. Likewise, it no longer uses petridish but instead maintains its own optimized/simplified Petri net framework.

This is all a reaction to over-generalization. This (3rd? 4th?) rewrite of werkflow has aimed for simplicity in implementation over generalization simply for the sake of generalization.

werkflow is a flexible, extensible process- and state-based workflow engine. It aims to satisfy a myriad of possible workflow scenarios, from enterprise-scale business processes to small-scale user-interaction processes. Using a pluggable and layered architecture, workflows with varying semantics can easily be accomodated. Processes can revolve around documents, objects or any other entity.

Anyhow, check it out. Come chat on IRC. If you're in the South, let's have lunch, and I'll explain to you how everything is workflow and how everyone needs werkflow.

The Bouncy Castle has released version 1.17 of their cryptostuff.

Release 1.17 is now available for download. The SMIME/CMS classes now support compressed data, CMS supports encapsulated signed data, and SMIME now allows for the sending of binary files where base64 is not appropriate. RC2 processing now works for the full range of parameters, and the X509Name/Principal classes are now configurable when it comes to string processing (in other words you can now support any "standard" way of doing this you want). A few minor bug fixes have been made as well.

Who really needs anything besides rot-13? That's uncrackable, right?

Fast Reference for Mathematical Symbols was found by Dan Diephouse while reading up on Petri nets and needing to interpret the math symbols.

I've stumbled my way through many an academic paper just trying to guess the meaning of symbols from the contxet. Having this resource just rocks.