Cov txheej txheem:
Video: Yuav ua li cas koj rov qab ob npaug hauv Java?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Java. Lang. Ob chav kawm hauv Java
- toString(): Rov qab cov hlua coj mus rau qhov ob npaug tus nqi.
- valueOf(): xa cov Ob npaug khoom pib nrog tus nqi muab.
- parseDouble(): rov ob npaug tus nqi los ntawm parsing txoj hlua.
- byteValue(): rov qab tus nqi byte sib raug rau qhov no Ob npaug Yam khoom.
Ua li no, kuv yuav rov qab ntau yam khoom hauv Java li cas?
Rov qab ntau qhov tseem ceeb los ntawm ib txoj hauv kev hauv Java
- Rov qab Ib Yam Khoom lossis Sau Npe.
- Hloov cov khoom lossis List parameter.
- Rov qab ib tug Tuple nrog cov nqi.
- Rov qab ib qho khoom tsim nyog nrog cov txiaj ntsig raws li tus cwj pwm.
- lwm.
Ntxiv thiab, dab tsi yog ob npaug hauv Java nrog piv txwv? Wb pom ib piv txwv ntawm ntab, ob npaug , char thiab boolean tus nqi. Peb tau siv + koom nrog ob txoj hlua hauv tshooj kawg.
Cov ntaub ntawv hom hauv Java.
| Hom ntaub ntawv | Tus nqi siab tshaj | Yam tsawg kawg nkaus |
|---|---|---|
| ob npaug | 1.7976931348623157E308 | 4.9 E-324 |
| char | 65, 535 | 0 |
| luv | 32767 | -32768 |
| ntev | 9223372036854775807 | -9223372036854775808 |
Kuj kom paub, ua li cas koj rov qab qee yam hauv Java?
Java xav kom ib txoj kev tshaj tawm cov ntaub ntawv hom ntawm tus nqi uas nws rov qab. Yog ib txoj kev tsis rov qab los tus nqi, nws yuav tsum tau tshaj tawm rau rov qab los tsis muaj dab tsi. Txawm li cas los xij, txoj kev pop hauv chav kawm Stack rov qab cov ntaub ntawv siv hom: ib qho khoom. Cov txheej txheem siv cov rov qab los tus neeg teb xov tooj rau rov qab los tus nqi.
Kuv yuav rov qab ob arrays hauv Java li cas?
Qhov zoo tshaj plaws, koj yuav tsum faib cov kev suav thiab rov qab los ntawm arrays nyob rau hauv lawv tus kheej txoj kev. Yog int/String arrays sawv cev rau qhov tseem ceeb / tus nqi khub, ces siv tau siv daim ntawv qhia DST kev siv (https://download.oracle.com/javase/6/docs/api/ java ua /util/Map.html) hloov thiab rov qab los uas. Koj tuaj yeem iterate tshaj qhov tseem ceeb / nqi raws li qhov tsim nyog.
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