02-服務(wù)計(jì)算基礎(chǔ)(分布式計(jì)算技術(shù)基礎(chǔ))(編輯修改稿)
2025-02-08 07:15 本頁面
【文章內(nèi)容簡介】 many applications may share, but which are not as fundamental as the Object Services ? . facility ? Application Objects: products of a single vendor on inhouse development group that controls their interfaces. CORBA應(yīng)用程序結(jié)構(gòu) CORBA中間件體系架構(gòu) Interface Repository Implementation Repository IDL Compiler Client Object Dynamic Invocation IDL Stub ORB Interface IDL Skeleton Dynamic Skeleton Object Adapter ORB Core GIOP/IIOP ORB(Object Request Broker) ?功能：提供一組服務(wù)邏輯 ?定位遠(yuǎn)程對象，傳輸請求，等待結(jié)果返回并在結(jié)果返回時(shí)將它傳給客戶端 ?實(shí)現(xiàn)對象位置透明 ?與開發(fā)語言無關(guān)：接口翻譯和語言綁定 ?優(yōu)點(diǎn) ?客戶端不必知道與服務(wù)器對象通信、激活或保存服務(wù)器對象的機(jī)制 ?不必知道服務(wù)器對象的位置、編程語言、操作系統(tǒng)以及其他非對象接口的系統(tǒng)信息 Client Object Object Request Broker (ORB) IDL(Interface Definition Language) ?中性語言 , 語言映射 ?模塊化對象接口 ?可描述對象支持的操作（方法）和屬性 ?可描述操作的異常定義 ?可描述操作返回值的數(shù)據(jù)類型、操作的參數(shù)和對象的屬性 Client Object Request Broker (ORB) IDL Stub IDL Skeleton Object CORBA請求響應(yīng)過程 ORB CORE In args Object Client Obj. ref. Operation () Out args + return value IDL Stub 1C Locate target object 3C 2C Send request to server Wait for request to plete Implementation Repository 1S Activate server IDL Skeleton 2S Activate Object’s Servant 3S Process Request 4S Return Request 4C Return Control to Client CORBA 互操作 Client ORB 1 IDL Stub IDL Skeleton Object Client IDL Skeleton Object ORB 2 IDL Stub IIOP Interoperability uses Inter InterORB Protocol CORBA的缺陷 ?對象粒度小，通信負(fù)荷大 ?復(fù)雜，龐大，必須由精深技術(shù)專家使用 ?實(shí)現(xiàn)廠商平臺的私有化造成 CORBA所追求的互操作性難以實(shí)現(xiàn) ?標(biāo)準(zhǔn)更新緩慢 DCOM DCOM Client COM Runtime Component COM Runtime Sec
環(huán)評公示相關(guān)推薦
鄂ICP備17016276號-1