Question

I have rule configuration on UI which builds to Java POJO. How could I generate Drools DRL (to be passed to other component which will match facts, etc and returns true or false if rule matches).

Also I receive DRL file from database and in order to show rule on UI, I need to convert back to Java POJO.

Basiclly is there any tool or script that could convert between Java POJO and Drools DRL file? If not, what is the best way available?

Thanks much!

Answer 1

I am not sure what are your Java POJOs? Are they representing Rules, Patterns, Constraints, etc?

If so, Drools has an internal canonical model for representing all types of knowledge assets [1]. We do not recommend using it directly though, as it is an internal API and subject to change.

Another option for you is to use the actual rule descriptor builder API [2] to generate your rules dynamically [3].

Finally, if you have a web based UI and you want to allow users to author your rules in there, you have the option to embed guvnor’s rule editor into your own application [4].

Hope this helps.

[1] https://github.com/droolsjbpm/drools/tree/master/drools-compiler/src/main/java/org/drools/lang/descr

[2] https://github.com/droolsjbpm/drools/tree/master/drools-compiler/src/main/java/org/drools/lang/api

[3] https://github.com/droolsjbpm/drools/blob/master/drools-compiler/src/test/java/org/drools/lang/api/DescrBuilderTest.java

[4] http://www.plugtree.com/guvnor-embed-asset%E2%80%99s-editor-in-your-application/