I am a complete novice concerning Drools and have some basic questions, which arised after studying the drools documentation and some examples as well. As far as I got it right, you have two possibilities to work with drools 1) You write a java program, rules / actions are hard coded inline or saved in text files / excel sheets / XML files etc. After importing the necessary drools classes you call the drools interface routines, with the following functionalities: load rules, providing working memory, adding facts und finally starting the rule engine (e.g. firing rules). 2) You use the capabilities of the Drools GUI tools (such as Guvnor), which allows entering rules, objects and actions via GUI tools. Here, I don't get the point whether a part of the java code is generated automatically, or whether you have to write your java classes by yourself, as presented in possibility 1 (above), but without coding the rules by yourself in the source code / external input files. I would be very pleased, if anyone could explain me the essential difference between the two approaches and accordingly tell me what the advantage of using method 2) would be in contrast to method 1), particularly concerning the necessary java coding. --- Well and there would be another question, if you write down your rules and the corresponding software, which accesses the rules, is it possible to add some rules later, without rewriting/recompiling your software? Thanks in advance! Cheers, Martin. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

I'm just wanna add some comments 2011/2/3 Esteban Aliverti <esteban.aliverti(a)gmail.com&gt; Hi, > > 1) You write a java program, rules / actions are hard coded inline or > saved > in text files / excel sheets / XML files etc. After importing the > necessary > drools classes you call the drools interface routines, with the following > functionalities: > load rules, providing working memory, adding facts und finally starting > the rule > engine (e.g. firing rules). > > Just some corrections here. The steps would be: load rules, get a working > memory (kbase), create a session from the working memory, insert facts to it > (this will start the pattern matching algorithm), fire the action part of > the rules that matches the inserted Facts. > The working memory is the knowledge session (not the kbase) where all your facts will live. The main advantage of this approach is to have the business rules / logic decoupled from your application and declarative expressed. Remember that the rule engine will not evaluate the rules in a sequential order (in contrast with IF and CASE statements) and the rule engine design was conceived thinking to handle huge amount of rules and the evaluation of these rules are optimized. > > 2) You use the capabilities of the Drools GUI tools (such as Guvnor), > which > allows entering rules, objects and actions via GUI tools. > Here, I don't get the point whether a part of the java code is generated > automatically, or whether you have to write your java classes by yourself, > as > presented in possibility 1 (above), but without coding the rules by > yourself in > the source code / external input files. > > Guvnor is just used as a centralized place to create (if you want to), > maintain and distribute your rules. You have different editor for different > representations, like DRL, BRL (using a Guided Editor), Decision Table, DSL, > etc. Guvnor then exposes these assets (their source code or binary > representation) through different URLs. So, your application should read the > rules (in the first step of the previous section) from Guvnor using HTTP (or > even webdav) to create the working memory. > > Hope this helps to clarify a little bit your thoughts. > > Best Regards, > > > XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX > > Esteban Aliverti > - Developer @ http://www.plugtree.com > - Blog @ http://ilesteban.wordpress.com > > > > On Thu, Feb 3, 2011 at 2:26 PM, Martin Richardsen <jaichwill(a)gmail.com&gt;wrote: > >> >> I am a complete novice concerning Drools and have some basic questions, >> which arised after studying the drools documentation and some examples as >> well. >> >> As far as I got it right, you have two possibilities to work with drools >> >> 1) You write a java program, rules / actions are hard coded inline or >> saved >> in text files / excel sheets / XML files etc. After importing the >> necessary >> drools classes you call the drools interface routines, with the following >> functionalities: >> load rules, providing working memory, adding facts und finally starting >> the rule >> engine (e.g. firing rules). >> >> 2) You use the capabilities of the Drools GUI tools (such as Guvnor), >> which >> allows entering rules, objects and actions via GUI tools. >> Here, I don't get the point whether a part of the java code is generated >> automatically, or whether you have to write your java classes by >> yourself, as >> presented in possibility 1 (above), but without coding the rules by >> yourself in >> the source code / external input files. >> >> I would be very pleased, if anyone could explain me the essential >> difference >> between the two approaches and accordingly tell me what the advantage of >> using >> method 2) would be in contrast to method 1), particularly concerning the >> necessary java coding. >> >> >> --- >> >> >> Well and there would be another question, if you write down your rules >> and the >> corresponding software, which accesses the rules, is it possible to add >> some >> rules later, without rewriting/recompiling your software? >> >> >> Thanks in advance! >> >> Cheers, Martin. >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > -- - CTO @ http://www.plugtree.com - MyJourney @ http://salaboy.wordpress.com - Co-Founder @ http://www.jbug.com.ar - Salatino "Salaboy" Mauricio - _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users