Koj tuaj yeem tshawb xyuas yam khoom twg yog Java?
Koj tuaj yeem tshawb xyuas yam khoom twg yog Java?

Video: Koj tuaj yeem tshawb xyuas yam khoom twg yog Java?

Video: Koj tuaj yeem tshawb xyuas yam khoom twg yog Java?
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Koj ua tau xyuas hom khoom hauv Java los ntawm kev siv qhov piv txwv ntawm lo lus tseem ceeb. Kev txiav txim siab hom khoom Nws yog ib qho tseem ceeb yog tias koj tab tom ua cov khoom sau xws li ib qho array uas muaj ntau tshaj ib qho hom ntawm khoom . Piv txwv li, tej zaum koj yuav muaj ib qho array nrog cov hlua thiab cov lej sawv cev ntawm tus lej.

Ua li no, koj txiav txim siab li cas hom khoom?

Java muab peb txoj kev sib txawv rau nrhiav tus hom ntawm khoom hauv runtime e.g. piv txwv ntawm lo lus tseem ceeb, getClass() thiab isInstance() txoj kev ntawm java. lang. Chav kawm . Tawm ntawm tag nrho peb tsuas yog getClass() yog qhov uas raws nraim nrhiav hom ntawm khoom hos lwm tus kuj rov qab muaj tseeb yog tias Hom ntawm khoom yog tus super hom.

Koj yuav ua li cas xyuas seb qhov sib txawv yog ib txoj hlua hauv Java? Cov Java piv txwv ntawm lo lus tseem ceeb yog siv rau kuaj yog tias ib yam khoom yog ib yam. Nws rov qab muaj tseeb lossis cuav. Piv txwv li, peb ua tau xyuas seb puas muaj qhov sib txawv yog hom Txoj hlua ; peb ua tau xeem chav kawm kom pom yog lawv yog tej yam (piv txwv li, yog Birch ib tsob ntoo lossis ib tug tub npe?).

Ib yam li ntawd, hom khoom hauv Java yog dab tsi?

Ib khoom yog ib qho piv txwv tshwj xeeb ntawm chav kawm nrog nws tus kheej lub xeev. A Java Cov ntawv tshaj tawm hauv chav kawm piav txog cov ntsiab lus tseem ceeb ntawm ib qho twg khoom ntawm chav kawm: Cov tswv cuab cov ntaub ntawv: Cov hloov pauv uas sawv cev rau lub xeev ntawm cov khoom . Methods: Programming code uas siv ntau yam khoom kev coj cwj pwm.

Kuv yuav nrhiav tau qhov piv txwv ntawm Java li cas?

piv txwv ntawm yog ib lo lus tseem ceeb. Nws tshawb xyuas yog tias qhov khoom siv yog ib qho piv txwv ntawm ib hom, thiab xa rov qab tus nqi boolean; Cov piv txwv ntawm Yam khoom yuav rov qab muaj tseeb rau txhua qhov khoom siv tsis yog null, txij li tag nrho Java cov khoom tau txais los ntawm Object.

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