Video: Koj ua tiav cov ntaub ntawv abstraction li cas?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Abstraction yog xaiv cov ntaub ntawv los ntawm lub pas dej loj dua kom pom tsuas yog cov ntsiab lus cuam tshuam rau cov khoom. Nws pab txo cov programming complexity thiab siv zog. Hauv Java, abstraction yog ua tiav siv Abstract chav kawm thiab interfaces. Nws yog ib lub tswv yim tseem ceeb ntawm OOPs.
Ua raws li qhov kev pom no, koj ua li cas thiaj li ua tiav abstraction?
Hauv java, abstraction yog ua tiav los ntawm interfaces thiab abstract classes. Interfaces tso cai rau koj kom paub daws qhov kev ua tiav tag nrho thaum cov chav kawm paub daws teeb meem tso cai ib feem abstraction ib yam nkaus. Cov ntaub ntawv abstraction spans los ntawm kev tsim cov ntaub ntawv yooj yim rau kev siv cov khoom siv nyuaj xws li HashMap lossis HashSet.
Ib yam li ntawd, cov ntaub ntawv abstraction ua tiav hauv DBMS li cas? Data Abstraction hauv DBMS . Database systems yog tsim los ntawm complex cov ntaub ntawv cov qauv. Txhawm rau kom yooj yim rau cov neeg siv kev sib cuam tshuam nrog cov ntaub ntawv, cov neeg tsim khoom zais cov ntsiab lus tsis sib xws los ntawm cov neeg siv. Cov txheej txheem no zais cov ntsiab lus tsis cuam tshuam los ntawm tus neeg siv hu ua cov ntaub ntawv abstraction.
Ua raws li qhov xav tau, cov ntaub ntawv abstraction ua tiav hauv C ++ li cas?
Abstraction txhais tau tias tsuas yog tso tawm cov ntaub ntawv tseem ceeb thiab zais cov ntsiab lus. Cov ntaub ntawv abstraction hais txog tsuas yog muab cov ntaub ntawv tseem ceeb ntawm cov cov ntaub ntawv mus rau lub ntiaj teb sab nraud, zais cov ntaub ntawv keeb kwm yav dhau los lossis kev siv. Abstraction siv Chav Kawm: Peb tuaj yeem siv tau Abstraction hauv C++ siv cov chav kawm.
Dab tsi yog cov ntaub ntawv abstraction vim li cas thiaj xav tau abstraction?
Cov ntaub ntawv abstraction hais txog kev muab nkaus xwb qhov tseem ceeb cov ntaub ntawv rau lub ntiaj teb sab nraud thiab zais lawv cov ntaub ntawv keeb kwm yav dhau, i.e., los sawv cev rau xav tau cov ntaub ntawv hauv qhov kev zov me nyuam yam tsis tau nthuav tawm cov ntsiab lus.
Pom zoo:
Dab tsi yog cov ntaub ntawv yooj yim tsim los ua thiab nws ua tiav cov haujlwm no li cas?
Lub hom phiaj tseem ceeb tshaj plaws ntawm cov ntaub ntawv kaw lus yog tswj cov neeg siv cov ntaub ntawv. Qhov no suav nrog khaws cia, rov qab thiab kho cov ntaub ntawv. Qee lub tshuab ua ntaub ntawv lees txais cov ntaub ntawv khaws cia raws li cov kwj ntawm bytes uas tau sau thiab khaws cia kom zoo rau kev tshaj tawm
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Dab tsi VM Series koj yuav tsum xav txog yog tias koj xav tau cov ntawv thov host uas xav tau kev ua haujlwm siab IO rau cov ntaub ntawv tsis tu ncua?
Teb: VM series uas koj yuav tsum yog xav txog yog tias koj xav tau txais cov ntawv thov uas xav tau kev ua haujlwm siab rau cov ntaub ntawv tsis tu ncua yog VMware workstation, Oracle VM virtual box lossis Microsoft Azure suav. Cov khoom siv no muaj qhov yooj yim tshaj plaws ntawm kev ua haujlwm hosting
Dab tsi yog cov teeb meem ntawm kev tswj cov ntaub ntawv hauv cov ntaub ntawv ib txwm muaj?
Nyob rau tib lub sijhawm, qhov kev tswj hwm cov ntaub ntawv ib puag ncig tsim teeb meem xws li cov ntaub ntawv rov ua dua thiab tsis sib xws, cov kev pab cuam-cov ntaub ntawv dependence, inflexibility, tsis muaj kev ruaj ntseg, thiab tsis muaj cov ntaub ntawv sib qhia thiab muaj
Yuav ua li cas koj rov qhib cov ntaub ntawv ua tsis tiav hauv Testng?
Cov kauj ruam ua raws li: Tom qab thawj qhov kev khiav haujlwm ntawm kev sim ua haujlwm. Txoj nyem rau ntawm Project - Nyem rau Refresh. Ib daim nplaub tshev yuav raug generated hu ua "test-output" folder. Hauv "test-output" folder, koj tuaj yeem pom "testng-failed. xml" Khiav "testng-failed. xml" txhawm rau ua tiav qhov kev sim ua tsis tiav dua