Video: Dab tsi yog metadata ntawm chav kawm hauv Java?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Nws yog tus qauv ntawm cov loaded chav kawm base li Java khaws cia ntawm lub sijhawm ua haujlwm txhawm rau txhawm rau thauj khoom, txuas, JIT suav sau, thiab ua tiav Java code. Cov kev xaiv tsim sib txawv uas koj ua thaum sau koj cov lej tuaj yeem nthuav dav lossis cog lus tus nqi ntawm metadata Java yuav tsum khaws cia.
Ib yam li ntawd, metadata hauv Java yog dab tsi?
Metadata hauv paus txhais tau tias cov ntaub ntawv uas muab cov qauv piav qhia txog qee cov ntaub ntawv. Java Metadata cov ntaub ntawv muaj txiaj ntsig tshwj xeeb rau kev sau cov lej uas tuaj yeem hloov mus rau ntau qhov system database lossis rau cov ntsiab lus ntawm ib qho database.
Dab tsi yog qee qhov piv txwv ntawm metadata? Qee qhov piv txwv ntawm qhov yooj yim metadata yog tus sau, hnub tsim, hnub hloov kho, thiab cov ntaub ntawv loj. Metadata Nws kuj tseem siv tau rau cov ntaub ntawv tsis muaj teeb meem xws li cov duab, yeeb yaj kiab, nplooj ntawv web, cov ntawv nthuav qhia, thiab lwm yam. Cov nplooj ntawv Web feem ntau suav nrog metadata nyob rau hauv daim ntawv ntawm meta tags.
Kuj Paub, dab tsi yog metadata hauv Java nrog piv txwv?
Muab qhov ntawd metadata yog ib txheej ntawm kev piav qhia, qauv thiab kev tswj xyuas cov ntaub ntawv hais txog ib pawg ntawm cov ntaub ntawv hauv computer (rau piv txwv xws li database schema), Java Metadata Interface (los yog JMI) yog lub platform-nruab nrab specification uas txhais cov creation, cia, nkag mus, nrhiav thiab pauv ntawm metadata hauv Java programming
Dab tsi yog metadata thiab vim li cas nws tseem ceeb?
Metadata Nws yog ib qho tseem ceeb rau kev tswj xyuas cov ntaub ntawv keeb kwm ntawm cov ntaub ntawv mus sij hawm ntev, ua rau muaj qhov tsis sib xws uas tuaj yeem tshwm sim hauv kev sau cov ntaub ntawv, cov neeg ua haujlwm thiab cov txheej txheem. Kev dav metadata tseem tuaj yeem ua kom cov ntaub ntawv tsim los rau ib lub hom phiaj kom rov qab siv tau rau lwm lub hom phiaj thiab lub sijhawm ntev dua.
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