Jazoon ’09: Experience with Rules Engines
Session title: Java Rule Engines (JBoss’ Drools, IBM’s iLog)
From: Raed Haltam, WEGA Informatik
Claim: Rules engines can reduce development time.
Raed makes the valuable clarification that a usable Rules Engine needs to address storage, versions, security etc. and is therefore best described as a Business Rules Management System (BRMS). He also takes care to distinguish the Business Object Model (BOM) from the Execution Object model (XOM).
Both iLog and Drools use the algorithm RETE. All rules follow the format:
when X then Y
Rules can be grouped into packages.
Both iLog and Drools allow higher level business language descriptions of rules.
Business rules can be made secure on various levels down to the statement level. In other words different editing privileges can be assigned to to different roles, which control the parts of a rule which can be edited under a given role.
Both tools support Complex Event Processing, which amounts to responding to patterns of conditions in a predefined way.
Raed presents a convincing sounding car financing case study from (JPMorgen Chase.) Rule deployment takes place at 8pm and are executed from 8am the following day.
Conclusion: Quite a nice, objective short summary (it was a short talk after all) on business rules for those unfamiliar with the technology.
