Video: Enum piv li cas hauv Java?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Enum Implements Comparable interface thiab nws yog piv rau () txoj kev sib piv tib yam nkaus xwb enum . Kuj ntuj txiav txim ntawm yog enum qhov kev txiav txim uas lawv yog tshaj tawm nyob rau hauv code. Raws li pom nyob rau hauv 10 piv txwv ntawm Enum hauv Java , tib order yog kuj tswj los ntawm ordinal() txoj kev ntawm enum , qho yog siv los ntawm EnumSet thiab EnumMap.
Hauv qhov no, dab tsi yog enum hauv Java?
Java Enums . Ib enum yog ib qho tshwj xeeb "chav kawm" uas sawv cev rau ib pawg ntawm qhov tsis tu ncua (tsis hloov pauv hloov tau, zoo li qhov kawg hloov pauv). Tsim ib qho enum , siv cov enum lo lus tseem ceeb (es tsis yog chav kawm lossis qhov sib txuas), thiab cais cov qhov tsis tu ncua nrog tus lej cim.
Ib yam li ntawd, puas yog enum piv? Enum tas li xwb piv rau lwm tus enum tsis tu ncua ntawm tib yam enum hom. Qhov kev txiav txim ntuj tsim los ntawm txoj kev no yog qhov kev txiav txim uas tau tshaj tawm tas li.
Raws li txoj cai, enum piv nrog txoj hlua li cas?
Rau piv String rau Enum hom koj yuav tsum hloov enum rau txoj hlua thiab tom qab ntawd piv lawv. Rau qhov koj tuaj yeem siv toString() txoj kev lossis lub npe() txoj kev. toString() - Rov qab lub npe ntawm qhov no enum tas li, raws li muaj nyob rau hauv daim ntawv tshaj tawm.
Koj piv cov khoom hauv Java li cas?
Yuav tau piv ob Java khoom ntawm tib chav kawm boolean sib npaug ( Yam khoom obj) txoj kev yuav tsum tau overriden thiab siv los ntawm chav kawm. Tus neeg siv txiav txim siab seb qhov twg yuav tsum sib npaug los xav txog ob khoom kom sib npaug.
Pom zoo:
Dab tsi yog enum hauv Java nrog piv txwv?
Ib hom enum yog hom ntaub ntawv tshwj xeeb uas ua rau muaj qhov sib txawv los ua ib pawg ntawm cov ntawv teev tseg ua ntej. Qhov sib txawv yuav tsum sib npaug rau ib qho ntawm qhov tseem ceeb uas tau hais ua ntej rau nws. Cov piv txwv muaj xws li cov lus qhia ntawm cov lus qhia (NORTH, SOUTH, EAST, thiab WEST) thiab hnub ntawm lub lim tiam
HashMap siv li cas hauv Java nrog piv txwv?
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