ApacheOFBiz学习基础手册专业资料

ApacheOFBizGettingStartedApacheOFBiz之旅TOC\o"1-3"\h\u79261.ApacheOFBiz简介 2102561.1TheWhat，WhyandHowofApacheOFBiz 2251791.2.HowDoIDecideWhattoUse? 2295372.SecondPartMailingLists 3323953.DemoandTestSetupGuide示例和安装指南 5267623.1.Introduction 5300893.2.Quick&EasySetup 5259323.3.BuildingFromSVN 6109263.4.DatabaseSetup 7209183.5.J2EEContainers 860224.TheOpenForBusinessProject：EntityEngineConfigurationGuide 8ApacheOFBiz简介这个档和有关文档信息内容来开始咱们OFBiz之旅。Thisdocumentandit'srelateddocumentscontaininformationaboutgettingstartedwithOFBiz.阅读这编文档后你也允许以得到某些协助同步也开始了ApacheOFBiz精彩世界之旅。AfterreadingthisdocumentyoumightfindthesehelpfulaswellasyougetstartedonyourjourneyintothewonderfulworldofApacheOFBiz:MailingLists(邮件发送清单)DemoandTestSetupGuide(示例测试指南)TechnicalProductionSetupGuide(技术产品指南)BusinessSetupGuide(业务指南)OFBizSourceRepositoryandAccess(OFBiz源码库和通道)FrameworkIntroductionVideosandDiagrams(框架简介视频和图表)OFBizBeginnersDevelopmentGuideUsingPracticeApplicationOFBizContributorsBestPracticesTheWhat，WhyandHowofApacheOFBizThebasicstructureanddrivingforcebehindOFBizhasalottodowiththegoalsandactualizationofthereleaseprocess.OFBizisandalwayshasbeenacommunity-drivenopensourceproject.ThereisnocentralcommercialorganizationthatdrivesthedevelopmentofOFBizorderivesaprojectfromtheintellectualpropertyofthesoftwareorotherprojectassets.ThisisformalizednowthatOFBizisaprojectintheApacheSoftwareFoundation.BecauseofthisOFBizalwayshasbeenandalwayswillbejustwhatuserswhocontributetotheprojectwantittobe.Therearemanydifferentindividualsandgroupsinvolvedwithmanydifferentneedsandourgoalistodefineandfollowdevelopmentandreleasepoliciesthatservetheneedsoftheseparties.So，let'sstartwiththat...HowDoIDecideWhattoUse?FromaprojectuserperspectivethereisonemainquestionthatcanhelpdeterminewhichwaytheywillwanttogetOFBiz：DoIwanttocontributetotheopensourceproject?Forthisquestionthereare3mainanswers:Yes，definitely：Iwanttocontributetodesign，coding，andtestingeffortsandtherebycollaboratewithotherstomoreeffectivelyandefficientlysatisfythelong-termrequirementsfromme，myclients，ormyemployerKindof：Iwanttostayonthecuttingedgeandparticipatewithtestingandfeedback，butI'mnotinapositiontoparticipateindevelopmentand/orinthenearfutureIwillneedsomethingmorereliableandsupportedandthatwon'tchangeverymuchNotreally：I'mhappytoofferfeedback，butIreallyneedsomethingthatwillworkwellnowandwellintothefuturesowecangetthingsgoinginourorganizationForeachanswerthereisarecommendedwaytogetOFBiz:Getthecodestraightfromthecoderepository(SVN)trunkandupdatefrequentlythroughdevelopment，stoppingbeforeyourintegrationorfinalpre-deploymenttesting，andperiodicallyevenafterproductiondeploymentaccordingtoyourongoingdevelop/deployplan；notethatwhenyouarenotupdatingfromSVNyoushouldcontinuetowatchthecommitsforbugfixestopatchintoyourcodebaseGetthecodefromthecoderepository(SVN)releasebranchandkeepupdatedorpatchedregularlyasfixesarecommittedandthebranchstabilizesovertime；whengettingstartedchoosethemostrecentbranch，evenifitisverynew；whennewreleasebranchesarecreatedupdatetothemsoonafterthebranchisdoneGetabuiltreleasepackageorthecodefromareleasebranchtag，andupdateasnewpre-builtreleasepackagesandtagsarecreated；thesewillonlyrepresentfixesandunlessamajorissuearisestheywillbebackwardcompatibleandgenerallysafetoupdateorpatchto；whengettingstartedchooseareleasebranchthathasbeenaroundforatleast2-3monthsandthathasnomajoroutstandingissuesintheissuetrackertoassurethatithasstabilized；whennewreleasebranchesarecreatedwaituntilyouarereadytodoamajorupgradeandpossiblyneedtomodifyyourcodeandconfiguration，andwaitatleastuntiltheprospectivebranchhasstabilizedbeforemovingtoitSecondPartMailingListsTosubscribetoamailinglistusethelinksbelow.InyourfirstemailyouwillgetsomeinformationaboutworkingwiththelistmanagerEZMLM.

Tounsubscribefromanyofthefollowinglists，youneedtosendanempty，subjectlessemailtounsubscribeaddresslistedbelow.Inotherwords，clicktheappropriateunsubscribelinkbelowandpresssend.SupportofUsersandDevelopersList：Theuserlistisintendedforinstallation，deployment，customdevelopmentandusagerelatedtopics.HighTrafficSubscribeUnsubscribeArchives

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Elsepleasefollowthisscenario(atleatrelevantparts)WhyWhatyouwerelookingforHowdidyoutrytoachieveitWhatdidyouexpectasresultsAndwhatyoureallygotHowWhatyoudid(includingdetailedstepstoreproduce)WhatyouexpectedtohappenWhatactuallyhappened(includingexactquotesoferrormessages，etc)IfpossibleprovideanURLDesignanddevelopmentList：ThedeveloperlistisstrictlyfortopicsrelatedtothedesignanddevelopmentoftheOFBizProjectitself.

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PluginsearchtoolsforFirefoxusingNabbleorMarkMailHistoryForhistoryyoumaylookatdevusersvnJiraThereisnoembeddedsearchtoolbutyoumayusegooglesitesearchoptionSearchinginthewikiAsConfluencewikiissharedamongprojectsattheASF，ifyouwanttosearchonlyforOFBizinformationyoucanusetheOFBizAdvancedSearchpage.Oryoucanfollowthesesteps:Addthe5OFBizspaces(orwhateveryouwant)intoyourfavoritespaces.Forthat，browseandclickonthe'Star'besidesanyspacestoadd，orifyouseeanystarsthere，whilstinaspaceclickonTools>Favorite.Thestarshouldgoyellow.Clickinthesearchboxandpressentertogettheadvancedsearch(Whichshouldbringyouto)Typeinyoursearchtermthenchoose'FavoriteSpaces'fromthe'Where'dropdownbox.Clickonfilter.Resultsfromonlythespacesyouhaveaddedtofavoriteswillbeshown.PersonnalyIhavealsoaddedthe5spacesaswatchestoreceiveeverydayasummaryofchangesinthesespace.Thisalsobuildyouacorrectdashboard(MyDashboard).DemoandTestSetupGuide示例和安装指南Introduction这编文档描述了OFBiz安装和业务项目基本配备选项。关于更详细简介请看OFBizFrameworkConfigurationGuide，EntityEngine(database)ConfigurationGuide，ServiceEngineConfigurationGuide，和OFBizDocumentationIndexthisdocumentdescribesaninitialsetupprocessandbasicconfigurationoptionsfortheOpenForBusinessProject.FormoredetailseerelateddocumentssuchastheOFBizFrameworkConfigurationGuide，theEntityEngine(database)ConfigurationGuide，theServiceEngineConfigurationGuide，andotherrelateddocumentsyoumayfoundatOFBizDocumentationIndexIfyourunintotroubletherearevariousresourcesavailabletohelp.ThefirststepswouldbetosearchontheNewOFBizDocsSiteandOldOFBizWiki(nowarchived)，andthenontheOFBizMailingLists.Ifyoucan'tfindyouanswerthere，thensubscribetotheApacheOFBizUsersMailingList，andsendamessagewithasmuchdetailaspossibleabouttheproblemyouarehaving.Quick&EasySetupYoucangetupandrunningquicklybydownloadingtheOFBizCompletedistributionandfollowingsomesimpleinstructions.Formoreoptionsandexplanations，seetherestofthisdocument.DownloadandinstalltheJava2v1.5seriesJDK/J2SDK(nottheJRE，youneedthefullSDK)fromSun'sJava(J2SE)siteifyouintenttouseareleasepriortoR10.04ortrunkelseuse1.6，andmakesureyourJAVA_HOMEenvironmentvariableissettothisJDKafterinstallation(NOTEthatforMacOSXnoJVMsetupisneeded，justmakesureJavaisuptodatewiththeOSXSoftwareUpdatefacility).NotealsothatOpenJdkisstillnotrecommended，therearestillsomecompilationproblmemswithit(today：-05-27)DownloadtheOFBizreleasearchiveandunzipitinthedirectoryofyourchoice(seecommentsbelowaboutthat，sofornowcheckingoutofSVNrepositoryispreferred，seebelow...).Thisshouldcreateonesub-directory：ofbiz.ThiswillbetheOFBIZ_HOMElocation.StartOFBizwithembeddedTomcatbygoingintotheofbizdirectoryandthenrunning"startofbiz.bat"(or"%JAVA_HOME%\bin\java-jarofbiz.jar")forWindows，or"./startofbiz.sh"(or"$JAVA_HOME/bin/java-jarofbiz.jar")forLinux/Unix.ForOSXyoucanjustrun"java-jarofbiz.jar"andyoudon'tneedtosetuptheJAVA_HOMEoranythingbecauseitisalreadythere.Openabrowserandgoto:8080/ecommerce/control/mainfortheecommerceapplicationor:8443/webtools/control/mainfortheWebToolsapplicationor:8443/catalog/control/mainfortheCatalogManagerapplication.Thedefaultadministrativeaccountisusername："admin"，password："ofbiz".Havefunwithit！YouarerunningonaJavadatabase.Formorediscussionofdatabases，readthesectionbelowonthattopic.Formoredetailedoptionsandconfigurationinformation，readon!BuildingFromSVNWhenbuildingfromSVNyouwillneedtohaveaJava1.5seriesJ2SDK(NOTjusttheJRE，needtofullSDK)asmentionedabove，forreleasepriortoR10.04ortrunkelseuse1.6.ThebuildisdoneusingAnt，andsufficientAntlibrariesareincludedwithOFBiz.IfyouhaveAntinstalledseparatelyjustmakesureyouhaveversion1.5orlater，andthenrunAntasnormalinteadofaslistedinthefollowingexamples.InthedirectorywhereyouwantOFBiztobe，doaSVNcheckoutoftheofbiztrunk.Forexample:svncoofbizForinformationonconnectingtoSVNclickhere.Nowgointothe"ofbiz"directoryandrun"ant.bat"(Windows)，or"./ant"(Linux/Unix/OSX).Itwillcompileallmodulesandleaveyouanexecutablejar(ofbiz.jar)inthe"ofbiz"directory.Toloadtheseedanddemodata，run"ant.batrun-install"or"%JAVA_HOME%\bin\java-jarofbiz.jarinstall"(Windows)，or"./antrun-install"or*"$JAVA_HOME/bin/java-jarofbiz.jarinstall"*(Linux/Unix/OSX)Asanalternativetothepreviousstep：toloadtheseeddataonly，run"ant.batrun-install-seed"or"%JAVA_HOME%\bin\java-jarofbiz.jarinstall-readers=seed"(Windows)，or"./antrun-install-seed"or*"$JAVA_HOME/bin/java-jarofbiz.jarinstall-readers=seed"*(Linux/Unix/OSX)Tostarttheserverrun"ant.batrun"or"%JAVA_HOME%\bin\java-jarofbiz.jar"(Windows)，or"./antrun"or"$JAVA_HOME/bin/java-jarofbiz.jar"(Linux/Unix/OSX)AnotherbuildoptionintheAntbuildscriptthatisusefulis"ant.batclean"(Windows)or"./antclean"(Linux/Unix/OSX).Thatwillcleanoutallbuiltclassesallowingyoutorun"ant"againtogetacleanbuild.IfyouarerunningintofunnyerrorsafterupdatingfromSVNinthefuture，givethiscleanbuildprocessatryfirst.DatabaseSetupDatabasesetupisdoneintheentityengine.xmlfile.TherearemanyoptionstherewhicharedescribedintheEntityEngineConfigurationGuideTheOFBizpackagecomeswithDerby，anopensourceJavadatabasefromIBMthatcomplieswithDB2specsandisbasedontheCloudscapeproduct.Thisdatabaseisgoodfordemonstrationpurposesbecauseitiseasytosetupanduse.Itisnotthebestforlargedatasetsanddoesnotprovidethesameperformanceorscalabilitythatamajordatabasewould，butcomparedtoHypersonicSQL(thatweusedtouse)itissignificantlybetterbecausewhilenotasfastforsmallscaleoperationsitisclosertoaproductiondatabaseenvironmentandallowsustocatchissuesearlieron.Smallersitesmightevenconsiderthisasanoptionfortheirproductiondeployment，especiallyoncethedatabaseisabitmorestabilized.Therearemanyopensourcedatabasesthatwillscalewellanddelivergoodperformance.ThetwomostpopulararePostgreSQLandMySQL(4.1.11orlater，orthe5series).Postgresisaveryfullfeatureddatabasewithtransactionsupport，foreignkeys，storedprocedures，etcetera.Postgresalsohasveryfriendlylicenseterms.MySQLisaprettygoodoptionthesedaysaswell.PleasenotethatifyouusethisinacommercialproductioninstanceyoumayhavetopurchaseacommerciallicensebecauseitisGPLlicensedandsoistheJDBCdriver.MySQLABallowsuseoftheJDBCdriverinopensourceprojectsinspitetheGPLlicense，butthismaynotapplyforcommercialuseofamodifiedOFBiz.Forsomeacommerciallicenseisthepreferredwaytogoanywaybecauseofsupportandwarrantyandotherissues.ForthosewiththispreferenceconsideringPostgresthereisalsoacommercialPostgresderivativecalledEnterpriseDB.Commercialdatabasesarealsosupported.Ifyouhavedatabaselicensesforotherneeds，orhavemajorin-housefamiliaritywithandsupportforacertaincommercialdatabase，thenthereisnoreasonnottotakeadvantageofthat.OFBizhasbeentestedwithOracle，DB2，Sybase，MSSQLServerandothersandshouldworkfinewithanydatabasethathasaJDBCdriver.PleasenotethatwehaveexperiencedthatinsomecasestheJDBCdriversincludedwithcertaindatabasesarenotfullyspecificationcompliant.Theoptionsareoftentousethedatabase-specificAPIsortogetathirdpartydriver.Thedatabase-specificcodeisanissuebecauseoflicensingrestrictionsandadditionaldifficultyneededtokeepupwiththem，sosometimesathirdparty(evenacommercialone)ispreferred.ForexamplewithOraclewehavehadmuchmoresuccesswiththeDataDirectJDBCdriver.ThereisnoneedtorunanySQLscriptstocreatethetablesorpopulatethemwiththedefaultdata.Theentityenginecancreatemissingtablesorfieldswhentheserverstartsupanddoessoiftheappropriatepropertyissetintheentityengine.xmlfile.Thisisthefilethatconfigurestheserversfortheentityengine.Forthetablecreationroutinetoworkproperly，thefieldtypesmustbesetup.DothisbyspecifyingthecorrespondingfieldtypeXXX.xml(whereXXXisthedatabasename)filefortheserverintheentityengine.xmlfile.ThesefieldtypeXXX.xmlfilesarelocatedintheofbiz/framework/entity/fieldtypedirectory.Defaultdatacanbeloadedthroughthe"run-install"AnttargetasmentionedintheBuildingfromSVNsection.J2EEContainersOFBizcomesandrunsbydefaultwithTomcatforaServlet/JSPcontainer，theApacheGeronimoTransactionManagerforatransaction(JTA)manager，andApacheDBCPforatransactionawareconnectionpool.OFBizcanalsobeconfiguredtorunindifferentcontainers，buttheremaybeissueswithcertainquirksthatothercontainershave，especiallywithservletcontainers.Wehavealwaysbeenabletofindwork-aroundsforthese，buttheyalsoseemtokeeponappearing，sothatisjustsomethingtowatchfor.BecauseofthedifficultyofdeployinginanexternalapplicationserverwehavecreatedaconfigurationandscripttemplatetoolthattakestheclasspathandwebappsettingsfromthevariousOFBizfilestomoreeasilygeneratethefilesyouneed.Formoreinformation，seetheREADMEfileintheofbiz/framework/appserversdirectory.IfyouarelookingforagoodcommercialJ2EEappserver，Orionisagoodplacetostart，butwerecommendtryingoutTomcatandGeronimoTMandseeiftheymeetyourneeds.TheOpenForBusinessProject：EntityEngineConfigurationGuideWrittenby：DavidE.Jones，Minorcorrectionsby：PawelH.DebskiEditedby：LesAustin

LastUpdated：August6，TableofContentsRelatedDocumentsIntroductionResourceLoadersJTAElementsDelegatorElementsEntityModelXMLFilesEntityGroupXMLFilesEntityECAXMLFilesFieldTypeXMLFilesDataSourceElementsRelatedDocuments:EntityEngineGuideFrameworkConfigurationGuideServiceEngineConfigurationGuideXMLFileDefinitions(DocumentsPage)IntroductionThisdocumentdescribestheconfigurationoftheEntityEngine.Itstartswithanintroductiontogeneralideasandthengoesthrougheachpartoftheentityengine.xmlfileandexplainstheavailableelementsandtheirusage.Theentityengine.xmlfileusedfortheOFBizapplicationshasexamplesofanumberofdifferentoptionsandislocatedinofbiz/commonapp/etc/entityengine.xml.TheconfigurationoftheEntityEngineisdonethroughasimpleXMLfilecalledentityengine.xmlthatmustexistsomewhereontheclasspath.ThisfileisusedtodefineparametersforpersistenceserverssuchasEJBserverparametersorJDBCserverparameters.ItisalsousedtospecifywhichXMLentitymodel，entitygroup，andfieldtypemodelfileswillbeusedforthatserver.ThedefaultfilefortheOFBizdistributioncanbefoundinofbiz/commonapp/etc/entityengine.xml.EachapplicationthatusestheEntityEnginedoessothroughaGenericDelegatorinstance.Thedelegatornamemustbepassedtothestaticfactorymethodthatisthenpassedtotheconstructorifanewinstanceisneeded.Thisdelegatornameisusedtolookupsettingsforthatdelegatorintheentityengine.xmlfile.Eachdelegatorusesanentitymodelreaderandanentitygroupreaderthatspecifiesagroupnameforeachnamedentityintheentitymodelfile.Theentityengine.xmlfilecontainsthesettingsthatmapeachgroupnametoaGenericHelperforthatgroup.GenericHelperisaninterfacethatmustbeimplementedforeachtypeofdatasource(i.e.：JDBC，EJB，SOAP，HTTP，etcetera).ThesettingsforeachnamedGenericHelperarespecifieddatsourceelementsintheentityengine.xmlfile.ForaJDBChelperthesewouldincludedatabaseconnectionparameterssuchaseithertheJNDIdatasourceparametersortheJDBCparametersincludingthedrivername，theJDBCURI，andtheusernameandpasswordforthedatabase.AnEJBhelperwouldcontainJNDIparameterssuchasthecontextproviderURL，theinitialcontextfactory，andtheURLpackageprefixes.TheGenericDelegatoristheprimaryaccessmethodforEntityEngineservices.EachservicerequestisdispatchedtothehelperthatcorrespondstotheentitythattheserviceisrequestedforaccordingtothegroupnameoftheentityspecifiedintheentitygroupXMLfileandthehelperforthatgroupspecifiedintheentityengine.xmlfile.ThedefaultentitygroupXMLfilefortheOFBizentitymodelcanbefoundinofbiz/commonapp/entitydef/entitygroup.xml.ResourceLoadersTheresource-loadertagisusedtoconfigureanamedresourceloaderthatcanbeusedelsewheretoloadXMLandotherresources.Ithasthefollowingattributes.AttributeNameRequired?DescriptionnameYThenameoftheresourceloader.Usedinothertagsinthe"loader"attribute.classYTheclasstousethatextendstheabstractclassorg.ofbiz.entity.config.ResourceLoader.AvailableclassesincludeFileLoader，UrlLoader，andClasspathLoader，allinthesamepackageastheResourceLoaderclass.prepend-envNThenameofaJavaenvironmentpropertytoputattheverybeginningofthefulllocation，beforetheprefix.Thisisoptional.prefixNAstringtoputbeforethelocationwhenmakingthefulllocation.Thisisoptional.Ifusedwillgoaftertheprependedenvironmentpropertyandbeforethelocationspecifiedforeachresource.JTAElementsForJTAsupporttheEntityEngineneedsaccesstothejavax.transaction.UserTransactionandoptionallythejavax.transaction.TransactionManagerinterfaceimplementationsfortheTXManagerbeingused.Theseareretrievedthroughtheorg.ofbiz.entity.TransactionFactoryclass.Thisclassusestheclassspecifiedwiththeclassattributeofthetransaction-factory.ThisclassmaybechangeddependingonwhichapplicationserverortransactionmanageryouarerunningOFBizon.ThedefaultTXManagerisJOTMfromObjectWebandthefactoryclassforJOTMisorg.ofbiz.entity.transaction.JotmFactory.ThereisalsoaspecialclassforWeblogic：org.ofbiz.entity.transaction.WeblogicFactory，whichmustbechangedtoincludetheWeblogicspecificstuffandthencompiledwithweblogic.jarontheclasspath.Themostwidelyusefultransactionfactoryclassistheorg.ofbiz.entity.transaction.JNDIFactoryclass.Thisclassusessomeadditionalelementsfromtheentityengine.xmlfiletolocatetheUserTransactionandTransactionManagerobjectsinJNDI.Theuser-transaction-jndiandtransaction-manager-jnditagsareusedtospecifytheobjectnamesinJNDIandthenameoftheJNDIServertouse，asconfiguredabove.Bothtagshavetworequiredattributes：jndi-server-nameandjndi-name.Anexamplejndi-namefortheUserTransactionobjectisjava:comp/UserTransactionandfortheTransactionManagerobjectisjava:comp/TransactionManager.DelegatorElementsTheGenericDelagatoriscreatedthroughafactorymethodthattakesaStringargumentcontainingthedelegatorname.Thisdelegatornameisusedtolookupadelegatortagintheentityengine.xmlfile.AttributeNameRequired?DescriptionnameYThenameoftheDelegator.Usedtolookupthistagbydelegatorname.entity-model-readerYThenameoftheentity-model-readertouseforthisdelegator.entity-group-readerYThenameoftheentity-group-readertouseforthisdelegator.entity-eca-readerNThenameoftheentity-eca-readertouseforthisdelegator.IfnotspecifiednoEntityECAswillbeused.distributed-cache-clear-enabledNUsedtospecifyifthedistributedcacheclearshouldbeenabled.Ifnotspecifieddefaultsto"false".IfsettotruetheotherDCCattributeswillbeused.distributed-cache-clear-class-nameNUsedtospecifyifthenameoftheclasstouseforDCCandthatimplementsthedistributedcacheclearinterface.Ifnotspecifieddefaultsto"org.ofbiz.entityext.cache.EntityCacheServices"，whichisagooddefaultformostcasesthatusestheServiceEngineforconfigurationandremotecalls.distributed-cache-clear-user-login-idNUsedtospecifyiftheuserLoginId(touseforanysecuritychecks)isneededrelatedtodistributedcacheclearoperation.Ifnotspecifieddefaultsto"admin".Thedelegatortagmustcontainoneormoregroup-maptagsspecifyingadatasourcetouseforeachgroupofentitiesthatthedelegatorwillknowaboutfromtheentity-group-reader.Thedelegatorusesthisfiletoassignagrouptoeachentity.WhenanoperationonanentityisperformeditlooksupthegroupandthedatasourcehelperthatcorrespondstothegroupandusesthatHelpertoperformlowerlevelDataSourceoperations.WiththistechniquewhentheapplicationiswrittenitdoesnothavetoknowwhichHelperisresponsibleforagivenentity，andcanthereforehandleanentityorgroupsofentitiesassignedtodifferentDataSourceswithasimpleconfiguration.EntityModelXMLFilesTheentity-model-readertagisusedtoconfigureeachnamedentitymodelreader.Thetaghasanameattributeusedtospecifytheentitymodelreader'sname.Eachreadermayloadfrommultipleresourcesthatareeachspecifiedwitharesourcetaginsidethemaintag.Eachresourcetaghastworequiredattributes：loaderwhichspecifieswhichresource-loadertouseandlocationwhichspecifiesthelocationthattheresource-loaderwilluseinsideitselftoloadtheresource.EntityGroupXMLFilesTheentity-group-readertagisusedtoconfigureeachnamedentitygroupreader.Thetaghasanameattributeusedtospecifytheentitygroupreader'sname.ThegroupreaderusesXMLfilestogettheentity-groupmappings.Thetaghastwooptionalattributes：loaderwhichspecifieswhichresource-loadertouseandlocationwhichspecifiesthelocationthattheresource-loaderwilluseinsideitselftoloadtheresource.Thereisalsoasub-elementnamed"resource"thathasthesesameattributesandcanbeusedtospecifyadditionresourcesforadditionfiles.EntityECAXMLFilesTheentity-eca-readertagisusedtoconfigureeachnamedentityECAreader.ThetaghasanameattributeusedtospecifytheentityECAreader'sname.TheECAreaderusesXMLfilestogettheentityECAruledefinitions.Eachreadermayloadfrommultipleresourcesthatareeachspecifiedwitharesourcetaginsidethemaintag.Eachresourcetaghastworequiredattributes：loaderwhichspecifieswhichresource-loadertouseandlocationwhichspecifiesthelocationthattheresource-loaderwilluseinsideitselftoloadtheresource.FieldTypeXMLFilesThefield-typetagisusedtoconfigureeachnamedfieldtype.Thetaghasanameattributeusedtospecifythefieldtype'sname.ThegroupreaderusesasingleXMLfiletogetthefieldtypeinformation.Thetaghastworequiredattributes：loaderwhichspecifieswhichresource-loadertouseandlocationwhichspecifiesthelocationthattheresource-loaderwilluseinsideitselftoloadtheresource.DataSourceElementsManydatasourcescanbeconfiguredusingonedatasourcetagforeachdatasource.Thistaghasthefollowingattributes，andmaycontainthefollowingsub-elements:AttributeNameRequired?DescriptionnameYThatnameofthedatasource.helper-classYTherecanbemanytypesofdatasourcehelpers；themainoneusedistheJDBC/DAOhelper.Youcancodeyouownhelpersandusethembyimplementingtheorg.ofbiz.entity.GenericHelperinterface.ForJDBC/DAOhelperstheclasswillbeorg.ofbiz.entity.GenericHelperDAO.field-type-nameYThenameofthefield-typetouse.Mustmatchthenameofanexistingfield-typetagasdefinedabove.schema-nameNThenameoftheschematouseinthedatabase.Ifnotspecifiednoschemanamewillbeused.Thisisacasesensitivevalueandadifferentdatabasemayexpectadifferentcasing.check-on-startNCheckthedatasourceonstartup?Mustbetrueorfalse，defaultstotrue.add-missing-on-startNAddmissingentitiesandfieldstothedatasourceonstartupwhencheckingisdone?Mustbetrueorfalse，defaultstofalse.use-foreign-keysNUse/Createforeignkeysfor"one"relationships?Mustbetrueorfalse，defaultstotrue.use-foreign-key-indicesNUse/Createindicesforforeignkeys(i.e.anindexontheforeignkeycolumns)?Notethatcreatingforeignkeysisnotrequiredforthistoworkandthatindicesarecreatedfortype"one"relationshipdefinitions.Mustbetrueorfalse，defaultstotrue.