外文翻译-javarmi和corba

外文原文JAVARMIANDCORBAFROMJAVASERVERPAGESSPECIFICATIONVERSION12AUTHORKEVINYANKOFSITEPOINTCOMEJBWOULDNOTBECOMPLETEWITHOUTAWAYTOINTEGRATELEGACYSYSTEMSBYITSELF,EJBGIVESYOUPORTABLE,ENTERPRISECLASSSERVERSIDEAPPLICATIONSTHESEAPPLICATIONSCANBEDEVELOPEDRAPIDLYWITHOUTTHEMANAGEMENTOVERHEADOFHAVINGTOCONSTRUCTASCALABLE,SECUREENVIRONMENTCOMBININGTHISWITHCORBAALLOWSEJBCUSTOMERSTOLEVERAGELEGACYCORBAAPPLICATIONS,ASWELLASINTEGRATEWITHEXISTINGINVESTMENTSWRITTENINNONJAVALANGUAGESSUCHASCANDCOBOLINDEED,CORBAANDEJBAREVERYRELATEDMANYOFTHECONCEPTSINJAVA2PLATFORM,ENTERPRISEEDITIONCAMEFROMCORBAINTHISCHAPTER,WELLLEARNTHEHIGHLEVELCONCEPTSBEHINDCORBAWELLTHENSEEHOWJAVARMIANDCORBACANBECOMBINEDVIARMIIIOPFINALLY,WELLLOOKATHOWTOUSERMIIIOPANDCORBACLIENTSTOACCESSEJBSYSTEMSTOUNDERSTANDTHISCHAPTER,YOUMUSTFIRSTUNDERSTANDJAVARMIIFYOUAREUNFAMILIARWITHTHISTECHNOLOGY,PLEASEREADAPPENDIXABEFOREREADINGTHISCHAPTERWHATISCORBATHECOMMONOBJECTREQUESTBROKERARCHITECTURECORBAISAUNIFYINGSTANDARDFORWRITINGDISTRIBUTEDOBJECTSYSTEMSTHESTANDARDISCOMPLETELYNEUTRALWITHRESPECTTOPLATFORM,LANGUAGE,ANDVENDORCORBAINCORPORATESAHOSTOFTECHNOLOGIESANDISVERYBROADINSCOPECORBAWASINVENTEDBYTHEOBJECTMANAGEMENTGROUPOMG,ACONSORTIUMOFCOMPANIESTHATBEGANIN1989CORBAITSELFISSIMPLYASTANDARD,JUSTLIKEEJBTHECORBASPECIFICATIONISIMPLEMENTEDBYCORBACOMPLIANTPRODUCTS,SUCHASINPRISESVISIBROKERFORJAVA,IONASORBIXWEB,ANDSUNMICROSYSTEMSJAVAIDL,JUSTASTHEEJBSPECIFICATIONISIMPLEMENTEDBYEJBCOMPLIANTPRODUCTS,SUCHASBEASWEBLOGIC,IBMSWEBSPHERE,ANDORACLESORACLE8IPRODUCTSCORBAASTHEBASISFOREJBMANYOFTHECONCEPTSINEJBCAMEOUTOFCORBAINASENSE,YOUCANTHINKOFEJBASCORBAWITHANEWHATONEJBANDTHEJAVA2PLATFORM,ENTERPRISEEDITIONJ2EEBRINGAJAVACENTRIC,COMPONENTBASEDAPPROACHTOTRADITIONALMIDDLEWAREPROGRAMMINGANARCHITECTURESUITABLEFORRAPIDAPPLICATIONDEVELOPMENTCORBA,ONTHEOTHERHAND,OFFERSAMUCHBROADERSUITEOFMIDDLEWAREFEATURESWITHWHICHTOWORKTHISINCLUDESATIMESERVICE,ADISTRIBUTEDLOCKINGSERVICE,ARELATIONSHIPSERVICE,ANDMORETOUSECORBASSERVICES,YOUNEEDTOPROGRAMTOCOMPLEXMIDDLEWAREAPIS,WHICHINCREASETHELEARNINGCURVEFORCORBAPROGRAMMINGTHISISWHYEJBANDJ2EEAREMUCHMORESUITABLEFORRAPIDAPPLICATIONDEVELOPMENTTHANCORBAANDBECAUSEEJBISOFFICIALLYBEINGSUPPORTEDBYTHEINDUSTRYTHEREARE25VENDORSWRITINGEJBPRODUCTSATTHISTIME,EJBWILLGIVEYOUAMUCHWIDERVARIETYOFTOOLSTOWORKWITHINTHELONGRUNREGARDLESSOFTHIS,CORBAISAVERYIMPORTANTTECHNOLOGYANDISQUITEUSEFULFORADVANCEDMIDDLEWAREDEVELOPMENT,CROSSLANGUAGESUPPORT,ANDLEGACYINTEGRATIONINFACT,MOSTSERIOUSEJBPRODUCTSONTHEMARKETAREBASEDONCORBAANDUSECORBACONCEPTSBEHINDTHESCENESWHYSHOULDICAREABOUTCORBATOYOU,ASANEJBAPPLICATIONASSEMBLERORBEANPROVIDER,CORBAISIMPORTANTFORTHREEREASONSYOUCANUSECORBAFORLEGACYINTEGRATIONIFYOUHAVEANEXISTINGINVESTMENTSUCHASALEGACYBANKINGAPPLICATIONYOUCANLEVERAGETHATINVESTMENTTODAYUSINGCORBAFOREXAMPLE,LETSSAYYOUHAVEABANKINGAPPLICATIONWRITTENINCCORBAGIVESYOUTHEABILITYTOPRESERVEANDREUSEITYOUCANWRAPYOUREXISTINGINVESTMENTASACORBAOBJECT,ALLOWINGITTOBECALLEDFROMANYAPPLICATIONASWELLFINDOUT,CORBAISALANGUAGENEUTRALSTANDARDANDALLOWSCODEWRITTENINSEVERALLANGUAGESTOCOMMUNICATETHUSCORBAISANIDEALPLATFORMFORCODEWRITTENINDIFFERENTLANGUAGESTOCOOPERATECORBAALLOWSFORADVANCEDMIDDLEWAREDEVELOPMENTREMEMBERTHATEJBISNOTSUPPOSEDTOBEANENDALLTOEVERYPROBLEMBUTIFTHEREISAMIDDLEWARESERVICETHATCANBEGENERALIZED,YOURELIKELYTOFINDITSTANDARDIZEDASACORBASERVICEFORTHOSEWHONEEDIT,CORBAGIVESGREATFUNCTIONALITYCORBAANDEJBHAVEHOOKSCONNECTINGTHEMSOMEEJBPRODUCTSWILLALLOWYOURENTERPRISEBEANSTOBECALLEDFROMTWODIFFERENTKINDSOFCLIENTSCLIENTSWRITTENTOUSETHEJ2EESUITEOFAPISANDCLIENTSWRITTENTOUSECORBAAPISTHISMEANSTHATCODEWRITTENINCORSMALLTALKCANCALLYOURENTERPRISEBEANSBENEFITSOFUSINGCORBAWHYWOULDYOUWANTTOUSECORBATHEREAREMANYREASONSCORBAISNOTCONTROLLEDBYONECOMPANYBECAUSECORBAHASBEENINVENTEDBYACONSORTIUMOFCOMPANIES,THEREAREMANYPARTIESINVESTEDINCORBASSUCCESSTHISALSOMEANSTHATANYCHANGESTOTHECORBASPECIFICATIONAREVOTEDONJOINTLYTHISPREVENTSCORBAFROMBECOMINGASTANDARDTHATSSPECIFICTOONEPRODUCTORARCHITECTUREINTHEWAYTHATCOM,FOREXAMPLE,ISSPECIFICTOMSWINDOWSANDINREALITY,ENTERPRISEJAVABEANSISALSOTHEPRODUCTOFACONSORTIUMOFCOMPANIES,INCLUDINGIBM,ORACLE,SUN,ANDOTHERS,WHICHMEANSTHATEJBISALSONOTSTRICTLYCONTROLLEDBYONECOMPANYCORBAISLANGUAGEINDEPENDENTWHENYOUUSECORBA,YOUCANINVOKEMETHODSONOBJECTSWRITTENINOTHERLANGUAGESWITHOUTPROGRAMMINGINTHOSELANGUAGESTHISALLOWSFORVERYEASYLEGACYINTEGRATIONWITHLANGUAGESSUCHASCOBOLIFYOUREWRITINGYOURPROGRAMSINJAVA,YOUCANUSECORBAASANALTERNATIVETOTHEJAVANATIVEINTERFACEFORINVOKINGOBJECTSWRITTENINNATIVECODESUCHASCCORBAPROVIDESOPTIONALVALUEADDEDSERVICESVENDORSOFCORBAPRODUCTSCANADDOPTIONALFUNCTIONALITYTOENHANCEDEPLOYMENTSCOMMONSERVICESTHATMANYOBJECTSWILLNEED,SUCHASPERSISTENCE,SECURITY,TRANSACTIONS,ANDEVENTSDEVELOPERSWHOUSECORBADONTNEEDTOREINVENTTHEWHEELTHEYCANLEVERAGESERVICESWRITTENTOACOMMONSTANDARDBYANOTHERVENDORDRAWBACKSOFCORBAASUSUAL,THEWORLDISNTPERFECTUSINGCORBAHASDISADVANTAGESASWELLASADVANTAGESCORBAISSLOWMOVINGALLSTANDARDSCOMMITTEESAREBUREAUCRATICANDSLOWTOMAKEDECISIONSTHISISBECAUSETHESTANDARDSCOMMITTEEITSELFISNOTDRIVENBYREVENUES,BUTRATHERBYINDIVIDUALINTERESTSFROMPARTICIPATINGCOMPANIESCORBAEXPERIENCESBENEFITSFROMNOTBEINGOWNEDBYONECOMPANY,BUTITSOPENNESSISALSOADRAWBACKTHECYCLETIMEFORTHEOMGTOADOPTANEWCORBAFEATUREISONTHEORDEROFYEARSCORBAHASASTEEPLEARNINGCURVEASCORBAHASEVOLVEDOVERTHEYEARS,ITSUNDERGONE“FEATURECREEP”MOREANDMOREFEATURESHAVEBEENADDED,WHICHMAKESCORBAAROBUSTSTANDARDBUTALSOINCREASESTHELEARNINGCURVEINDEED,THESPECIFICATIONSTHATDEFINETHEWHOLEOFCORBAARETHOUSANDSOFPAGESLONGANDAREQUITECHALLENGINGTOMASTERTHENICETHINGABOUTCORBAISTHATYOUDONTHAVETOLEARNITALLTOUSEITTHEREAREOPTIONALCORBASERVICESTHATYOUCANLEARNASYOUNEEDTHEMPRODUCTSDEVELOPEDUNDERCORBAMAYHAVEINCOMPATIBLEFEATURESITSGREATTHATCORBAISAUNIFYINGSTANDARDBECAUSENOONECOMPANYCONTROLSTHESTANDARD,ITLEVELSTHEPLAYINGFIELDFORCOMPANIESCOMPETINGTOBUILDCORBAPRODUCTSBUTTHEREREMAINTHEPROBLEMSOFMULTIVENDORSOLUTIONSASWITHEJBPRODUCTS,IFYOUMIXANDMATCHCORBAPRODUCTS,YOUWILLINEVITABLYRUNINTOASSUMPTIONSTHATVENDORSHAVEMADEBUTTHATARESPECIFICTOTHEIROWNPRODUCTSTHISISTHETRADEOFFBETWEENAONEVENDORSOLUTION,SUCHASMICROSOFT,ANDANOPENSTANDARD,SUCHASCORBAOREJBTHEPRICEOFFREEDOMISETERNALVIGILANCEUNDERSTANDINGHOWCORBAWORKSBEFOREWEDELVEINTOCORBA/EJBINTEROPERABILITY,WELLCOVERTHECORECORBAFUNDAMENTALCONCEPTSTHISWILLLAYTHEGROUNDWORKFORUSTODISCUSSHOWCORBAANDEJBARECOMPATIBLEOBJECTREQUESTBROKERSANOBJECTREQUESTBROKERORORBISAFACILITATORFOROBJECTSONTHENETWORKTOCOMMUNICATEORBSAREINTERMEDIARIESBETWEENDISTRIBUTEDOBJECTSTHEYENABLEDISPARATEAPPLICATIONSTOCOMMUNICATEWITHOUTBEINGAWAREOFTHEUNDERLYINGCOMMUNICATIONSMECHANISMORBSALLOWOBJECTSTOCALLMETHODSONEACHOTHER,DYNAMICALLYDISCOVEREACHOTHER,ANDMOREORBSARERESPONSIBLEFORFINDINGOBJECTSTOSERVICEMETHODCALLS,HANDLINGPARAMETERPASSING,ANDRETURNINGRESULTSWHENEVERYOUHAVEMULTIPLEOBJECTSINTERACTINGINACORBAENVIRONMENT,ORBSFACILITATETHECOMMUNICATIONSTHISISSHOWNINFIGURE111THEREARENUMEROUSCORBAORBSONTHEMARKETSOMEEXAMPLESAREIONASORBIXWEB,INPRISESVISIBROKER,ANDIBMSCOMPONENTBROKEREACHVENDOROFFERSVARIOUSQUALITIESOFSERVICETHATDIFFERENTIATETHATVENDORSPRODUCTFROMTHOSEOFOTHERVENDORSINTHEMARKETPLACETHECONCEPTOFANORBISABSOLUTELYNOTSPECIFICTOCORBABOTHJAVARMIANDMICROSOFTCOMCONTAINORBFUNCTIONALITYASWELLBECAUSEBOTHRMIANDCOMFACILITATENETWORKCOMMUNICATIONSANDHENCESERVEASOBJECTREQUESTBROKERSFORTHERESTOFTHISCHAPTER,HOWEVER,WELLASSUMEWEREDEALINGWITHCORBAORBSWHATISIIOPTHROUGHOUTTHISBOOK,WEVESEENEJBAPPLICATIONSTHATCOMMUNICATEVIATHEJAVARMIAPIJAVARMIISACOMMUNICATIONSPACKAGEFORPERFORMINGDISTRIBUTEDCOMPUTINGINJAVABEHINDTHESCENES,JAVARMIUSESTHEJAVAREMOTEMETHODPROTOCOLJRMPASTHEDEFAULTPROTOCOLLAYERFORCOMMUNICATIONSTHECORBAWORLD,HOWEVER,DOESNOTUSEJRMPRATHER,CORBAPRODUCTSUSEADIFFERENTPROTOCOLCALLEDIIOPINTERNETINTERORBPROTOCOLIIOPISTHESTANDARDINTERNETPROTOCOLFORCORBAIIOP,JUSTLIKEJRMP,ISUSEDBEHINDTHESCENESFORDISTRIBUTEDOBJECTCOMMUNICATIONSCORBAORBSUSEIIOPTOCOMMUNICATEWITHEACHOTHER,ASSHOWNINOBJECTIMPLEMENTATIONSANDOBJECTREFERENCESCORBAPROVIDESACLEANSEPARATIONBETWEENANOBJECTSINTERFACEANDITSIMPLEMENTATIONWHENYOUWRITEACORBAOBJECTIMPLEMENTATION,THATOBJECTISCALLABLEOVERTHENETWORKBYREMOTECLIENTSTHOSECLIENTSDEALWITHYOURCORBAOBJECTIMPLEMENTATIONSINTERFACEONLYCLIENTSDONOTDEALDIRECTLYWITHYOUROBJECTIMPLEMENTATIONTHISSEPARATIONOFINTERFACEFROMIMPLEMENTATIONISQUITEANALOGOUSTOHOWDISTRIBUTEDCOMPUTINGISPERFORMEDINJAVARMIWITHBOTHCORBAANDJAVARMI,CLIENTSAREUNAWAREOFOBJECTIMPLEMENTATIONDETAILSCLIENTSARECONCERNEDONLYWITHTHEINTERFACESTOTHEOBJECTIMPLEMENTATIONSTHATTHEYAREUSINGINADDITIONTOINTERFACE/IMPLEMENTATIONSEPARATION,ONEOFCORBASGOALSISLOCATIONTRANSPARENCYOFDISTRIBUTEDOBJECTSLOCATIONTRANSPARENCYMEANSTHATCLIENTCODEISUNAWAREOFWHEREAREALOBJECTIMPLEMENTATIONRESIDESPERHAPSITISLOCAL,PERHAPSREMOTECORBAACHIEVESLOCATIONTRANSPARENCYWITHOBJECTREFERENCESANOBJECTREFERENCEISANIDENTIFIERFORAPARTICULAROBJECTIMPLEMENTATIONINCORBAITUNIQUELYIDENTIFIESTHEOBJECTIMPLEMENTATIONACROSSTHENETWORKANOBJECTREFERENCEAUTOMATICALLYTRACKSTHEOBJECTIMPLEMENTATIONITREPRESENTSBEHINDTHESCENESNOTETHATINTHEORY,YOUSHOULDNOTNEEDTOWORRYYOURSELFWITHTHEDETAILSOFOBJECTREFERENCESYOUSHOULDJUSTKNOWTHATTHEORBVENDORSUSETHEMINTERNALLYINTHEIRORBSTOIDENTIFYOBJECTSINREALITY,EACHVENDORSCORBAIMPLEMENTATIONDEALSWITHREFERENCESINASLIGHTLYDIFFERENTWAY,ANDYOUHAVETOKNOWHOWTOGETANOBJECTREFERENCEFROMEACHTYPEOFORBOBJECTADAPTERSACORBAOBJECTADAPTERISAPLUGGABLEENTITYTHATASSISTSINTHEFOLLOWINGTASKS_WHENANOBJECTISACCESSED,THEOBJECTADAPTERISRESPONSIBLEFORMAPPINGANOBJECTREFERENCEONTOANOBJECTIMPLEMENTATIONBEHINDTHESCENESWHENACLIENTPERFORMSANINVOCATION,THEORB,THEOBJECTADAPTER,ANDTHEIMPLEMENTATIONOBJECTCOORDINATETOFIGUREOUTWHICHIMPLEMENTATIONOBJECTSHOULDBECALLED_IFACLIENTCALLSAMETHODONANOBJECTIMPLEMENTATIONTHATISNOTINMEMORY,THEOBJECTADAPTERACTIVATESTHEOBJECTORINITIALIZESITINTOMEMORYSOITCANSERVICETHECLIENTREQUESTTHECONVERSEISALSOTRUEOBJECTADAPTERSALSODEACTIVATEOBJECTSACTIVATIONISAGREATHELPBECAUSEITGIVESCLIENTSTHEILLUSIONTHATSERVERSIDEOBJECTSAREALWAYSUPANDRUNNING,EVENTHOUGHTHEYARELAZYLOADEDACTIVATEDINTOMEMORYONTHEFLYCORBAWASDESIGNEDTOBEFLEXIBLEWITHOBJECTADAPTERSTHEYARETRULYPLUGGABLEENTITIESYOUCANHAVEMANYDIFFERENTKINDSOFOBJECTADAPTERSRUNNINGINYOURSYSTEM,WITHDIFFERENTKINDSOF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NEYOUROBJECTSINTERFACESEITHERBECAUSEJAVASSYNTAXISSIMILARTOCOMGIDLMAPSTOCONCRETELANGUAGESIDLISONLYADESCRIPTIVELANGUAGEINTHATITDESCRIBESTHEINTERFACESTOYOUROBJECTSYOUCANNOT“EXECUTE”IDLNEITHERYOURCORBAOBJECTIMPLEMENTATIONSNORYOURCORBACLIENTSEVERSEEIDLYOUPROGRAMYOURCLIENTSANDOBJECTIMPLEMENTATIONSINWHATEVERLANGUAGEYOUREUSING,SUCHASJAVAORCBUTHOW,THEN,DOYOUREFERTOCORBAOBJECTSTHEANSWERISTHEOMGIDLMAPSTOSPECIFICLANGUAGES,SUCHASJAVAORCIFYOUGOTOTHEOMGWEBSITEWWWOMGORG,YOULLSEETHATTHEREARESPECIFICATIONSDETAILINGHOWOMGIDLMAPSTOVARIOUSLANGUAGESFORINSTANCE,THEREISANIDLTOJAVAMAPPINGSPECIFICATIONTHATDEFINESHOWIDLMAPSTOJAVAWITHTHEIDLTOJAVAMAPPING,THESTRINGTYPEINOMGIDLMAPSTOTHEJAVALANGSTRINGOBJECTINJAVATHUS,ITSIMPORTANTTOREALIZETHAT,ALTHOUGHIDLISALANGUAGE,ITISMOREOFANABSTRACTIONBECAUSEYOUNEVERWRITECLIENTCODEOROBJECTIMPLEMENTATIONSTHATUSEIDLFILESRATHER,YOUUSEIDLTODEFINETHEINTERFACESTOYOUROBJECTSANDTHENMAPTHATIDLINTOYOURPARTICULARLANGUAGEUSINGANIDLCOMPILERFOREXAMPLE,ANIDLTOJAVACOMPILERWOULDTAKEASINPUTANIDLFILEANDGENERATEJAVAINTERFACESFORYOUROBJECTIMPLEMENTATIONSONCETHISISDONE,YOUCANIMPLEMENTTHOSEINTERFACESINJAVAYOUCOULDTHENMAPTHEIDLTOADIFFERENTLANGUAGE,SUCHASC,BYUSINGANIDLTOCCOMPILERTHISWOULDALLOWYOUTOWRITECLIENTCODEINCTHATCALLSYOURJAVAOBJECTIMPLEMENTATIONS中文翻译JAVARMI和CORBA如果没有一种方式使剩下的系统结合为整体EJB是不完整的靠EJB自己，它能给你提供便携的、更高级别的服务器方面的应用。这些应用在没有必须建立一个可升级，安全的环境的管理之上一样可以快速的发展。这些应用结合CORBA允许EJB用户去促进遗留的CORBA的应用，同时与现有的输入进去的非JAVA语言例如C和COBOL结合为整体。的确，CORBA和EJB有非常多的联系很多在JAVA2平台中的概念，来自CORBA的企业版本。在这一章，我们将学习CORBA之后的更高级的概念。我们将了解JAVARMI和CORBA凭借RMIIIOP结合在一起。最后我们会看到如何使用RMIIIOP和CORBA进入EJB系统。什么是CORBA公共对象请求代理体系结构是一个统一标准的为书写分布式的对象系统。其标准是在操作平台，编程语言和货主编码（VENDOR）完全中立的。CORBA吸收了额很多技术而且有广泛的处理余地。CORBA是由目标管理组织发明的一个在1989年开始的公司联营的财团。CORBA本身就是一个简单的标准，就像EJB。CORBA的详细计划书是由依从于CORBA的产品生效的，就像INPRISESVISIBROKER为JAVA，LONASORBIXWEB,和MICROSYSTEMSJAVAIDL,就像EIB的详细计划书由依从于EBJ的产品生效的，就像BEASWEBLOGIC,IBMSWEBSPHERE,和ORACLESORACLE8I产品。CORBA是EJB的基础很多EJB中的概念都来自于CORBA在一定程度上，你可以认为EJB是CORBA的更新。EJB与JAVA2操作平台，企业版本（J2EE）使一个中心的JAVA，基础的零件更接近传统的中间设备的规划一个适合技术应用快速发展的体系机构。在另一方面，CORBA提供了一套更广泛的具有工作特点的中间设备。这些包括了一个时间的服务，一个分散连接的服务，一个相关联的服务等等。要想使用CORBA的服务，你需要为复杂的能为CORBA规划增加知识曲线中间设备APLS编制程序。这就是为什么EJB和J2EE比CORBA更适合技术应用快速发展。还有因为EJB是正式的由工业提供支持（于此同时有超过25的卖主VERDORS编写EJB产品）EJB将提供给你更多样式的用于工作的工具在未来长远的发展中。除了这些，CORBA是一项非常重要的技术对于高级的中间设备的发展，混合语言的支持和剩余部分的结合非常有用的。实际上市场上很多EJB的产品是基于CORBA的和使用CORBA概念为背景的。为什么我应当关心CORBA对于你，CORBA作为应用的汇编程序或者提供者，CORBA很重要有如下三个原因你可以使用CORBA去使遗留部分结合成为整体。如果你有现有的投资（就像遗留的银行的应用）你可以使用CORBA促使投资改变。例如，我们说你有一个使用C书写的银行应用。CORBA可以给你能力保护和重新使用它。你可以包裹你现有的投资作为CORBA的一个允许被任何应用访问的对象。正如我们所发现的，CORBA是一个中立语言的标准，并允许用几种语言编写的编码相互交流。因此CORBA是一个用不同语言编写编码并合作的理想平台。CORBA允许高级的中间设备发展。EJB并不被认为是对所有问题的终结。但是如果这有一种广泛的中间设备的服务，你可能会找出像它的标准就像CORBA服务。对于需要它的人，CORBA提供很强大的功能。CORBA和EJB由挂钩连接他们。一些EJB的产品将允许你的企业版的应用程序素材被来自两个不同种类的客户访问使用J2EE整套APLS的书面客户和使用CORBAAPLS的书面客户。这就意味着使用C编写的编码或者SMALLTALK能访问你的企业版的应用素材。使用CORBA的好处为什么你要使用CORBA，这由很多原因CORBA不是被一个公司所控制。因为CORBA的创造是由公司组成的联营企业，CORBA的成功有很多的投资组成部分。这也意味着对于CORBA详细计划任何的变化都是连带的表决出来的。这会阻止CORBA变