Data Flow Diagram (DFD) vs UML
Ib daim duab sawv cev ntawm cov ntaub ntawv ntws los ntawm lub kaw lus hu ua Data Flow Diagram (DFD). Kev tsim kho DFD yog ib qho ntawm thawj kauj ruam uas tau ua thaum tsim cov ntaub ntawv xov xwm. UML (Unified Modeling Language) yog ib hom lus qauv siv hauv cov khoom taw qhia software tsim. Thaum tsim cov khoom taw qhia software, UML yog siv los qhia thiab pom cov khoom uas ua rau software system. UML daim duab kos feem ntau yog sawv cev rau kev pom cov qauv thiab kev coj tus cwj pwm ntawm lub cev.
Data Flow Diagram (DFD) yog dab tsi?
A DFD yog cov duab sawv cev ntawm cov ntaub ntawv ntws los ntawm lub kaw lus. Kev tsim kho DFD yog ib qho ntawm thawj kauj ruam uas tau ua thaum tsim cov ntaub ntawv xov xwm. DFD qhia cov ntsiab lus zoo li cov ntaub ntawv uas yuav nkag mus rau hauv thiab tawm ntawm lub system, cov ntaub ntawv tau mus los ntawm lub kaw lus li cas thiab yuav ua li cas cov ntaub ntawv yuav khaws cia rau hauv lub system. Tab sis DFD tsis muaj cov ntaub ntawv hais txog lub sijhawm cov ntaub ntawv ntawm cov txheej txheem. Cov khoom tseem ceeb suav nrog hauv DFD yog cov txheej txheem, cov ntaub ntawv khaws cia, cov ntaub ntawv ntws thiab lwm qhov chaw. Thaum tsim DFD daim duab kos, cov ntsiab lus theem DFD yog kos ua ntej. Nws qhia txog yuav ua li cas tag nrho cov kab ke cuam tshuam nrog cov ntaub ntawv sab nraud thiab cov ntaub ntawv dab dej. Tom ntej no Qib 0 DFD yog tsim los ntawm kev nthuav dav cov ntsiab lus theem DFD. Qib 0 DFD muaj cov ntsiab lus ntawm cov sub-systems hauv qhov system thiab seb cov ntaub ntawv ntws los ntawm lawv li cas. Nws tseem muaj cov ntsiab lus hais txog cov ntaub ntawv khaws cia uas xav tau hauv qhov system. Yourdon & Coad thiab Gane & Sarson yog ob lub cim uas siv los kos DFDs.
UML yog dab tsi?
UML yog hom lus qauv siv hauv cov khoom taw qhia software tsim. UML muab kev muaj peev xwm los qhia thiab pom cov khoom uas tsim los ntawm software system. UML daim duab qhia feem ntau yog sawv cev rau kev pom cov qauv thiab kev coj tus cwj pwm ntawm lub cev. Kev pom cov qauv ntawm cov kab ke yog sawv cev siv cov duab kos xws li cov duab kos duab, cov duab kos duab sib xyaw, thiab lwm yam. Dynamic saib ntawm lub kaw lus yog sawv cev siv cov duab kos xws li kab kos duab, daim duab kos duab, thiab lwm yam. UML version 2.2 suav nrog kaum plaub daim duab, uas suav nrog xya daim duab rau sawv cev rau tus qauv saib thiab lwm yam xya sawv cev rau tus cwj pwm saib. Ntawm xya daim duab coj tus cwj pwm, plaub daim duab tuaj yeem siv los sawv cev kev sib cuam tshuam nrog lub kaw lus. Muaj cov cuab yeej siv tau rau UML qauv xws li IBM Rational Rose.
Dab tsi yog qhov txawv ntawm Data Flow Diagram (DFD) thiab UML?
A DFD yog cov duab sawv cev ntawm cov ntaub ntawv ntws los ntawm lub kaw lus, thaum UML yog cov qauv qauv siv hauv cov khoom siv software tsim. UML qhia cov chav kawm ntawm cov duab kos uas tuaj yeem siv los ua qauv qauv thiab tus cwj pwm ntawm software system. Yog li daim duab UML, thaum sib koom ua ke sawv cev rau cov ncauj lus kom ntxaws ntau dua ntawm kev siv DFD ib leeg. DFD muab lub ntsiab lus pib zoo kom nkag siab tias qhov system ua haujlwm li cas tab sis thaum tsim cov kab ke, UML daim duab xws li daim duab qhia chav kawm, daim duab kos duab, thiab lwm yam yuav muaj txiaj ntsig zoo.
