Video: Puas yog EJB tseem siv tau?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Zoo, EJB yeej muaj sia nyob thiab zoo heev hauv Java Persistence Architecture (JPA). JPA yog ib feem ntawm EJB3 tus qauv. Yog koj txhais tias tsoos EJBs nrog tej thaj chaw deb interfaces a là EJB 1.0, Kuv tsis tuaj yeem hais.
Yog li ntawd, Ejb siv qhov twg?
EJB taum yog tsim tshwj xeeb los siv kev lag luam logic ntawm koj daim ntawv thov. Xws li lawv muab kev pabcuam uas feem ntau xav tau thaum siv cov logic, xws li kev lag luam, txhaj tshuaj ntawm tus thawj tswj hwm ( siv rau JPA, Java Persistence API) thiab kev sib xyaw ntawm taum.
Ib yam li ntawd, lub hom phiaj ntawm EJB hauv Java yog dab tsi? EJB yog server-side software tivthaiv uas encapsulates kev lag luam logic ntawm ib daim ntawv thov. Ib EJB lub vev xaib muab lub sijhawm ua haujlwm rau lub vev xaib cuam tshuam nrog software, suav nrog kev ruaj ntseg hauv computer, Java servlet lifecycle tswj, kev ua lag luam, thiab lwm yam kev pabcuam hauv web.
Raws li txoj cai, Java Beans puas tseem siv?
Java taum lawv tus kheej yog tseem heev central rau Java web applications, tsuas yog tsis siv yuam kev raws li cov tswj hwm. Tshwj tsis yog tias koj tab tom tham txog lub npe zoo sib xws tab sis txawv Enterprise Java taum (EJBs), qhov twg cov lus teb yog, tsis ntau ntxiv lawm.
EJB moj khaum yog dab tsi?
EJB (Enterprise Java Beans) yog ib qho server-sab tivthaiv uas ua tiav cov kev lag luam tshwj xeeb. Nws ua rau kev txhim kho thiab kev xa tawm ntawm cov khoom siv raws li, muaj zog, muaj peev xwm ua tau zoo heev & kev lag luam kev lag luam.
Pom zoo:
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