外文文献-introduction of struts struts简介

毕业设计外文文献原文及译文INTRODUCTIONOFSTRUTSSTRUTS简介学生姓名学号系别专业指导教师2015年5月电子与计算机科学技术系网络工程INTRODUCTIONOFSTRUTS1TALKINGTHETALKTHISCHAPTEREXPLORESTHESTRUTSFRAMEWORKINDEPTHANDHIGHLIGHTSTHEBENEFITSSTRUTSCANBRINGTOYOURDEVELOPMENTEFFORTSWEBELIEVETHATONCEYOUCAN“TALKTHETALK”OFWEBARCHITECTUREANDDESIGN,YOUWILLBEBETTEREQUIPPEDTOUSESTRUTSWITHYOUROWNAPPLICATIONSWITHASOUNDOVERVIEWOFTHESTRUTSARCHITECTUREINPLACE,WEOUTLINETHESTRUTSCONTROLFLOWANDTHEWAYITHANDLESTHEREQUESTRESPONSEEVENTCYCLEAGOODUNDERSTANDINGOFTHISPROCESSMAKESITMUCHEASIERTOCREATEAPPLICATIONSTHATMAKETHEBESTUSEOFTHEFRAMEWORKCHOOSINGAWEBAPPLICATIONFRAMEWORKSHOULDNOTBEACASUALDECISIONMANYPEOPLEWILLUSETHISBOOK,ANDESPECIALLYTHISCHAPTER,ASPARTOFEVALUATINGSTRUTSFORTHEIRPROJECTACCORDINGLY,WECONCLUDETHISCHAPTERWITHACANDIDLOOKATTHESTRENGTHSANDWEAKNESSESOFTHESTRUTSFRAMEWORKANDADDRESSCONCERNSREGARDINGOVERALLPERFORMANCESTRUTSISDESIGNEDFORPROFESSIONALDEVELOPERSTOMAKEINFORMEDDECISIONS,PROFESSIONALSNEEDTOBEAWAREOFBOTHATOOLSCAPABILITIESANDITSLIMITATIONS2WHYWENEEDSTRUTSTODAYSWEBAPPLICATIONSARECRITICALCOMPONENTSOFTHECORPORATEMISSIONASALWAYS,DEVELOPMENTTEAMSNEEDTOBUILDAPPLICATIONSINRECORDTIME,BUTTHEYHAVETOBUILDTHEMRIGHTANDBUILDTHEMTOLASTJAVAWEBDEVELOPERSALREADYHAVEUTILITIESFORBUILDINGPRESENTATIONPAGES,SUCHASJAVASERVERPAGESANDVELOCITYTEMPLATESWEALSOHAVEMECHANISMSFORHANDLINGDATABASESJDBCANDENTERPRISEJAVABEANSEJB,FOREXAMPLEBUTWHATDOWEUSETOPUTTHESECOMPONENTSTOGETHERWEHAVETHEPLUMBINGANDTHEDRYWALLWHATELSEDOWENEED21ENTERSTRUTSTHECENTERPIECEOFSTRUTSISANMVCSTYLECONTROLLERTHESTRUTSCONTROLLERBRIDGESTHEGAPBETWEENMODELANDVIEWTHEFRAMEWORKALSOINCLUDESOTHERMISSINGPIECESDEVELOPERSNEEDTOWRITESCALABLE,LEADINGEDGEWEBAPPLICATIONSSTRUTSISACOLLECTIONOF“INVISIBLEUNDERPINNINGS”THATHELPDEVELOPERSTURNRAWMATERIALSLIKEDATABASESANDWEBPAGESINTOACOHERENTAPPLICATION22STRUTSCONTROLLERCOMPONENTSTHESTRUTSCONTROLLERISASETOFPROGRAMMABLECOMPONENTSTHATALLOWDEVELOPERSTODEFINEEXACTLYHOWTHEIRAPPLICATIONINTERACTSWITHTHEUSERTHESECOMPONENTSHIDENASTY,CUMBERSOMEIMPLEMENTATIONDETAILSBEHINDLOGICALNAMESDEVELOPERSCANPROGRAMTHESEDETAILSONCE,THENGOBACKTOTHINKINGINTERMSOFWHATTHEPROGRAMDOESRATHERTHANHOWITDOESITUSERSINTERACTWITHAWEBAPPLICATIONTHROUGHHYPERLINKSANDHTMLFORMSTHEHYPERLINKSLEADTOPAGESTHATDISPLAYDATAANDOTHERELEMENTS,SUCHASTEXTANDIMAGESTHEFORMSGENERALLYSUBMITDATATOTHEAPPLICATIONVIASOMETYPEOFCUSTOMACTIONASSHOWNINFIGURE22,STRUTSPROVIDESCOMPONENTSTHATPROGRAMMERSCANUSETODEFINETHEHYPERLINKS,FORMS,ANDCUSTOMACTIONSTHATWEBAPPLICATIONSUSETOINTERACTWITHTHEUSERWEUSEDTHESECOMPONENTSTOBUILDASTARTERAPPLICATIONINCHAPTER1INCHAPTER3,WEWALKTHROUGHUSINGTHESECOMPONENTSTOBUILDANOTHERSIMPLEAPPLICATIONTHEN,INCHAPTER4,WEPROVIDEADETAILEDOVERVIEWOFCONFIGURINGTHESECOMPONENTSLATERCHAPTERSPROVIDEMOREDETAILABOUTPUTTINGEACHCOMPONENTTOUSEWITHINYOURAPPLICATIONINPART4WEDEMONSTRATEUSINGTHECOMPONENTSINTHECONTEXTOFWORKINGAPPLICATIONSBUT,SINCETHISCHAPTERISTHEARCHITECTURALOVERVIEW,LETSGOAHEADANDINTRODUCETHEMAJORSTRUTSCOMPONENTSNOW23HYPERLINKSTOTHEAPPLICATIONDEVELOPER,AHYPERLINKISAPATHTOSOMERESOURCEINTHEAPPLICATIONTHISMAYBEAWEBPAGEORACUSTOMACTIONITMAYALSOINCLUDESPECIALPARAMETERSINSTRUTS,DEVELOPERSCANDEFINEAHYPERLINKASANACTIONFORWARDTHESEOBJECTSHAVEALOGICALNAMEANDAPATHPROPERTYTHISLETSDEVELOPERSSETTHEPATHANDTHENREFERTOTHEACTIONFORWARDBYNAMEACTIONFORWARDSAREUSUALLYDEFINEDINANXMLCONFIGURATIONFILETHATSTRUTSREADSWHENTHEWEBAPPLICATIONLOADSSTRUTSUSESTHEXMLDEFINITIONSTOCREATETHESTRUTSCONFIGURATION,WHICHINCLUDESALISTOFACTIONFORWARDSTHEXMLELEMENTTHATWOULDCREATEANACTIONFORWARDFORAWELCOMEHYPERLINKMIGHTLOOKLIKETHISTHISELEMENTWOULDCREATEANACTIONFORMJAVABEANWITHITSNAMEPROPERTYSETTOWELCOMEANDITSPATHPROPERTYSETTO/PAGES/INDEXJSPJSPPAGESANDOTHERCOMPONENTSCANTHENREFERTOTHEWELCOMEFORWARDTHESTRUTSFRAMEWORKWILLLOOKUPTHEWELCOMEACTIONFORWARDBEANANDRETRIEVETHEPATHTOCOMPLETETHEHYPERLINKTHISALLOWSDEVELOPERSTOCHANGETHEDESTINATIONOFALINKWITHOUTCHANGINGALLTHECOMPONENTSTHATREFERTOTHATLINKINMOSTWEBAPPLICATIONS,DETAILSLIKETHISAREHARDCODEDINTOJSPANDJAVACODE,MAKINGCHANGESDIFFICULTANDPRONETOERRORINASTRUTSAPPLICATION,THESEDETAILSCANBECHANGEDTHROUGHOUTTHEAPPLICATIONWITHOUTTOUCHINGASINGLEPAGEORJAVACLASS24HTMLFORMSTHEWEBPROTOCOLS,HTTPANDHTML,PROVIDEAMECHANISMFORSUBMITTINGDATAFROMAFORMBUTLEAVERECEIVINGTHEDATAASANEXERCISEFORTHEDEVELOPERTHESTRUTSFRAMEWORKPROVIDESANACTIONFORMCLASS,WHICHISDESIGNEDTOHANDLEINPUTFROMANHTMLFORM,VALIDATETHEINPUT,ANDREDISPLAYTHEFORMTOTHEUSERFORCORRECTIONWHENNEEDED,ALONGWITHANYCORRESPONDINGPROMPTSORMESSAGESACTIONFORMSAREJUSTJAVABEANSWITHACOUPLEOFSTANDARDMETHODSTOMANAGETHEVALIDATIONANDREVISIONCYCLESTRUTSAUTOMATICALLYMATCHESTHEJAVABEANPROPERTIESWITHTHEATTRIBUTESOFTHEHTMLCONTROLSTHEDEVELOPERDEFINESTHEACTIONFORMCLASSSTRUTSDOESTHEREST25CUSTOMACTIONSANHTMLFORMUSESANACTIONPARAMETERTOTELLTHEBROWSERWHERETOSENDTHEFORMSDATATHESTRUTSFRAMEWORKSUPPLIESACORRESPONDINGACTIONCLASSTORECEIVESUCHDATATHEFRAMEWORKAUTOMATICALLYCREATES,POPULATES,VALIDATES,ANDFINALLYPASSESTHEAPPROPRIATEACTIONFORMTOTHEACTIONOBJECTTHEACTIONCANTHENGETTHEDATAITNEEDSDIRECTLYFROMTHEACTIONFORMBEANHERESANEXAMPLEPUBLICFINALCLASSLOGONACTIONEXTENDSACTION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