Database driven rule engines in java

I need to develop an application to be able to define the rules through UI and save them to database and nee开发者_开发知识库d to execute them on some data coming from another source. Is there is a rule engine that supports my requirement? Drools seems to be declarative based but I need to load the execute the rules on the fly. I am new to this rule engine concept. Any suggestions please?

Have you taken a look at Drools Guvnor? It lets you save and edit rules, even test rules (which can be persisted on an RDBMS) on the fly, and then integrate (evaluate) them within your Java/JavaEE application. Even if you don't need all its fancy features (such as versioning, IDE integration, etc.) it belies your assumption that Drools can't load rules dynamically from a database.

Note, however, that Drools wasn't primarily designed to reason over facts stored in an RDBMS. Starting with Drools 4.0 you can pull in objects from external resources, such as an RDBMS using Hibernate, but if my understanding is correct these will be treated as time-constant facts and not inserted into working memory.