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Rules Engine

I develop applications for a state agency; we have several applications that have a number of validation rules that tend to change over time.  I'm considering using a rules engine, but I'm not familiar with rules engines (I have a cursory knowledge of BizTalk).  I'd really like to find something that would allow a domain expert to edit business rules with minimal input from developers.  Any suggestions regarding rules engines?

Hard Coded
Thursday, August 12, 2004

Thursday, August 12, 2004

ILog has a few different related products. Definitely not free, but well supported in my experience.

Thursday, August 12, 2004

The best rules engine I've used (and I've used quite a few) is the Eclipse engine from Haley Enterprises:

They also have a product called Authorete that is designed to allow non-technical users to author and otherwise manipulate the business rules in natural language:

Some other options:

Clips - an open source, public domain rule engine developed at NASA:

There is a textbook that uses CLIPS as its presentation language

JESS: A Java based engine developed at Sandia National Labs.  This one also has a book available:

OPSJ: The company that makes this has (had?) Charles Forgy, the guy who invented the Rete algortihm that underlies virtually every modern rule engine, as their Chief Scientist.  This one is blazingly fast (it uses something called the RETE-2 algorithm), but the integration into Java took some work:

Anyhow, there are a few to get started.  Here's a link to a page that links to others, as well as some other useful information.  Good luck:

rule writer
Thursday, August 12, 2004

Can anyone explain in simple terms to me what typical uses of a rules engine would be, and how a task would be accomplished with it? 

So the idea is you take the 'business rules' to somewhere that can be managed centrally and altered easily, then you don't need to change your application right?  Any experiences?  Does it work like this in practice?

Friday, August 13, 2004

Please tell me more about why Haley is the best.  I'm currently comparing it with Blaze Advisor.

Friday, August 27, 2004

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