Mandarax规则引擎调研.ppt

Mandarax规则引擎 Mandarax简介 Mandarax是一个规则引擎的纯Java实现 它支持多类型的事实和基于反映的规则 数据库 EJB等等 支持XML标准 RuleML0 8 它提供了一个兼容J2EE的使用反向链接的接口引擎 Mandarax不支持JAVA规则引擎APIJSR 94 LogicalObjectsofMandarax Rules Thetop levelconstructiscalledarule Aruleassociatesoneormanyprerequisiteswithoneconclusion Facts Theprerequisitesandtheconclusionarefacts Terms Therearethreedifferentkindsofterms constantterms variabletermsandcomplexterms Termsaretypedandmandaraxtypesare arbitrary javaclasses Mandarax内部机制 Mandarax用户界面 Backwardvs ForwardReasoning Themandaraxinferenceengineusesbackwardreasoning andthereferenceimplementationusesanobjectorientedversionofbackwardreasoningsimilartothealgorithmusedinProlog Backwardreasoningalgorithmsarebasedoformal syntactical reasoning Theytakeonlythesyntaxofthetermsandotherlogicalobjectsintoaccount AdvantagesintheBackwardReasoningApproach Inforwardreasoning additionalsoftwaremustwatchthesedatasourcesandmustpropagatechangesinthosedatasourcesinordertokeepthederivationstructureuptodate Afactbasemustbesynchronizedbeforeaqueryisissued mostbusinesssolutionsimplementapullmodel likeasalestransactioninitiatedbyawebstorecustomer SystemarchitecturesusingawebclientsandSQLdatabasesaresuallybasedonapullmodelastheyareusingrequestbasedprotocolssuchasHTTPandSQLnetworkprotocols SQLNetetc Thequerydrivenbackwardreasoningfitsperfectlyintothisarchitecture Manyrulesystemsareworkingonlargefactbases Forsuchsmallrulebases thereisnosignificantdifferenceregardingperformancebetweenbackwardandforwardreasoning mandaraxtakesadvantageofexistingtechnologiesmanaginglargefactbases 与其他规则引擎的比较 JBossRulesandMandaraxJbossRules的推理方式是forwardchaining 它对assert的对象反应 事件驱动的 Mandarax的推理方式是backwardchaining 你问它问题 它试图给你它知道的答案JBossRules规则引擎应用Rete算法的改进形式Rete II算法 从内部机制上讲 它使用了和Forgy的算法相同的概念和方法 但是增加了可与面向对象语言无缝连接的节点类型 Mandarax基于反向推理 归纳法 能够较容易地实现多个数据源的集成 例如 数据库记