Synchronize fee to client.docx

DefiningOffline

Overview
AnytimepersistentdatafunctionalityisintroducedintheS1EnterpriseTellerapplication,youmustcreateanofflinedatasourcethatisresponsibleforpassingthedatatotheofflineengine.Thisenginetakeswhatispassedtoitfromadatasourceandcopiesittotheclientmachine.Datasourcesmustbedefinedintheregistryschema,whichdefineswhentheygetexecuted,where,andhowoften.Theofflinedataisstoredinfilesontheclientside.YoucanretrievethedatafromthesefilesusingAPIsthatareprovided.Ifyouwanttoreadthedatainandstoretheminmemory,thenyouwillhavetowriteyourownclasstodothat.Theofflinedataisdividedintodifferentschemas:global,terminal,anduserprofile.Withineachofthese
Schemas,thereareschemaelementsforeachofthetypesofinformationyouwanttostoreintheofflinestore.Theschemaelementstouseandwhatdatasourcewillretrievethedataforitaredefinedintheregistryschema.Togettheschemainstance,youwouldusethefollowing:

Global—GlobalDataManager.getGlobalData()
Terminal—TerminalDataManager.getTerminalData()
UserProfile—UserProfileManager.getUserProfile(userName)

Onceyouhavetheschemainstance,thenyouusethemethodgetElement(name)togettheparticularelementinwhichyouareinterested.Thenameoftheelementcomesfromthenamelistedinthedefinedregistryschema.ThegetElementmethodreturnsaSchemaInstanceElement.ThiscaneitherbeaMultiSchemaInstanceElementoraSingleSchemaInstanceElementdependingonthecardinalitysetting.Fromthetwo,youcangetatthedatathatwasstoredforthiselement.
(Thisdataiswhatyourdatasourcereturnedwheninvoked).
HandsonExercise:
Synchronizeafeeratetotheclientandreadingitfromoffline
关于如何同步数据库数据到本地
在properties文件中配置meta.attribute.loaders

每次Teller客户端启动都会加载DesktopPersistenceAttributeLoader
DesktopPersistenceAttributeLoader会读取meta文件，然后根据文件的配置选择是否同步数据

是否同步数据是根据ttl（本地数据存在时间）这个配置来判断，单位S/秒，当本地数据的存在时间超过ttl的配置，Teller启动时就会同步数据，否则不会同步

DefiningOfflineRegistrySchema:

Theofflineregistryconfigurationisusedbytheofflineenginetodeterminehoweachdatasourceistobeexecuted,when,andhowoften.Itisdefinedinthedesktoppersistencesectionofanobject's.metafile.