Welcome to the wiki of page for JBoss Rules. Otherwise known as Drools 3. Please feel free to add your own tips/gotchas - you just need to signup for a jboss.com account (free and open to everyone). Currently the JBoss wiki is still on the jboss.com site so you will find the links for the naviation on the left may have change if you linked through from JBoss Labs, confusing I know. This will be resolved in next JBoss Portal release when JBoss Wiki will be properly integrated with Jboss Labs.
IMPORTANT note re manual/documentation for 4.0
The documentation is now up to date, the language reference is now comprehensive, but it always needs improvement. If you want to get involved in improving this your help would be very much appreciated, we use docbook with the XMLMind editor which si very esay to get into. We will soon be looking for people to help out with i18n of the docs.
We are now running the excellent Hudson build tool. Whenever a change is made, it will build. You can track it from https://hudson.jboss.org/hudson/job/drools/. To get the latest SNAPSHOT releases, go to https://hudson.jboss.org/hudson/job/drools/lastSuccessfulBuild/artifact/trunk/target/. After a commit, a new build is usually available 30-ish minutes later (if successful), depending on load/time of day etc.
ATTENTION Eclipse plugin
Eclipse GEF is now required. So if you want to use the plug-in, you will need to download the GEF from Here. Or, you can use the Eclipse update feature to locate GEF. The rules update site should soon be updated to automatically install GEF if you don't have it already (but it isn't now).
ATTENTION: converting Eclipse projects with 3.0.5 plug-in to 4.0.n version
The 4.0.n Eclipse plug-in Builder has been moved to a different package. If you have Drools projects developed with the 3.0.5 plug-in and then you install the 4.0.n plug-in, you will have to edit the .project files and update the plug-in Builder name. Go to the the top directory of the project, open .project, find the line with "org.drools.ide.droolsbuilderorg.drools.eclipse.droolsbuilder</name>". It should start working as soon as you save the change.
Eclipse plug-in v. 4.0.0 Installation Instructions for Rational Application Developer v. 7.0
To clarify - Drools is the project development name, our R&D play pen. JBoss Rules is productized stable branch of Drools with additional support, consultancy and training; backports of bugs will be applied to JBoss Rules, but almost never to Drools.
NOTE: There is also a complete manual for JBoss Drools, this wiki supplements the formal manual (see below for links).
Known issues and features to be implemented can be seen via the JBoss jira
This is an ideal way to get started quickly if you are an Eclipse user. (Refer to the manual)
Getting help or helping out
As normal, the maniacs can be found in the drools IRC room at irc.codehaus.org. Web client available for those behind a firewall http://irc.codehaus.org. Mark Proctor is known as "conan", and he is a vegetiarian, so he won't bite. The others are not though
Use the mailing lists. Use the "user" list for end user issues, "dev" for when you are mucking about with the internals.
Use jira to log issues.
Business Rules community A useful site especially for business rule analysis (your best buddies remember !)
From the download page there are samples to show of various aspects. Some samples may be found on the wiki from time to time which are more up to date/richer.
Its important to note that the default textual language input for Drools 3 and up is a non XML format (XML support will be coming shortly as an alternative). It uses an Antlr3 grammar to parse rules and compile. See the RuleLanguageFAQ for some more info.
There is an examples project you can download.
Drools Puzzles - (A Regular Drools Programming Contest)
Since August 2007 we have a regular programming contest for JBoss-Drools. Initiated by E.Zhao, open to everyone. See the JBoss-Drools puzzle page for details. You might even win a price...
TIPS, TRICKS & FAQ for users (rule developers)
Deploying BRMS on Tomcat 6, Jetty etc (some tweaks to libs are needed).
Dynamically add a property change listener to your beans This means you don't need to "modify" object changes
Tomcat (and JBoss AS) Issues and tricks - also applies to app servers that use tomcat or similar for JSP compilation
Drools library in JBoss AS- NullPointerException at org.drools.compiler.PackageBuilder.compile(Unknown Source) using JBossAS 4.0.4GA
Have problems with serialization? Then read this
Counting facts from the LHS
Rule patterns and practices
Tips for JBoss Rules developers/contributors
We have just moved to an ant driven build system (it uses maven 2 underneath, but you don't need to install maven yourself) due to complaints. See the manual for details on how to build.
Presentations (feel free to use as needed)
JBoss Rules is made available at the JBoss maven2 repository http://repository.jboss.com/maven2/ in the following direcotry http://repository.jboss.com/maven2/org/drools/. We do not currently upload to ibiblio, but community members are welcome.
Feel free to edit/add to this wiki - the aim of the wiki is not to be a manual, but to be a general "catch all" area for helpful tips and links. Also, articles and documentation may be entered here first, when its ready, it will then be formally moved into the manual for future reference. In the old Drools web site, the wiki was also the documentation, but for Drools 3 onwards, we are providing a formal manual for this purpose.
Many tips are from real world deployments, add more of your own Feedback/contributions are always appreciated. Its a wiki !
Information can still be located here
Design and Enhancement ideas
This section is for contributors (of ideas and code) or people interested in the future directions of JBoss Rules. Some of these ideas are works well in progress, some are just concepts/thoughts. Jump in, the water is warm (its a wiki !).