Video: Dab tsi yog override hauv Scala?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Scala Txoj kev Overriding . Thaum ib tug subclass muaj tib lub npe txoj kev raws li tau teev tseg nyob rau hauv cov niam txiv chav kawm ntawv, nws yog hu ua method overriding . Thaum subclass xav muab ib qho kev siv tshwj xeeb rau cov qauv uas tau teev tseg hauv cov chav kawm niam txiv, nws overrides txoj kev los ntawm niam txiv chav kawm.
Ntawm no, ua li cas koj override ib txoj hauv kev hauv Scala?
Hauv Scala , txoj kev overriding siv override modifier nyob rau hauv thiaj li yuav override a txoj kev txhais nyob rau hauv cov chav kawm super whereas, txoj kev overloading tsis tas yuav tsum muaj lo lus tseem ceeb lossis hloov kho, peb tsuas yog yuav tsum tau hloov pauv, qhov kev txiav txim ntawm qhov tsis siv lossis tus lej ntawm qhov tsis muaj. txoj kev los yog cov ntaub ntawv hom ntawm cov parameters
Tsis tas li ntawd, Scala puas txhawb nqa ntau yam qub txeeg qub teg? Scala tsis yog tso cai rau ntau yam qub txeeg qub teg per se, tab sis tso cai rau ncua ntau yam ntxwv. Cov cwj pwm yog siv los qhia cov interfaces thiab teb ntawm cov chav kawm. Lawv zoo ib yam li Java 8's interfaces. Cov chav kawm thiab cov khoom tuaj yeem txuas ntxiv qhov zoo tab sis qhov zoo tsis tuaj yeem ua sai sai thiab yog li tsis muaj qhov ntsuas.
Ua raws li qhov no saib, chav kawm twg Scala tau txais txiaj ntsig los ntawm?
Nws yog lub mechanism nyob rau hauv Scala los ntawm ib qho chav kawm yog tso cai rau qub txeeg qub teg cov yam ntxwv (teb thiab txoj kev) ntawm lwm tus chav kawm . Cov ntsiab lus tseem ceeb: Super Chav kawm : Cov chav kawm nws cov yam ntxwv yog qub yog hu ua superclass (los yog lub hauv paus chav kawm los yog niam txiv chav kawm ).
Dab tsi yog super chav kawm hauv Scala?
Hu rau tus txheej txheem ntawm a Super Class hauv Scala . Lub tswv yim no yog siv thaum peb xav hu chav kawm super txoj kev. Yog li thaum twg a puag thiab subclass muaj tib lub npe txoj kev ces daws qhov tsis meej pem peb siv super lo lus tseem ceeb hu chav kawm hauv paus txoj kev. Lo lus tseem ceeb “ super ” los rau hauv qhov no nrog lub tswv yim ntawm Inheritance.
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