Video: Dab tsi yog qhov txawv ntawm JDK 7 thiab JDK 8?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Java 7 nqa JVM kev txhawb nqa rau cov lus dynamically-typed ntxiv rau Hom Kev cuam tshuam rau Generic Instance creation. Java 8 nqa qhov kev cia siab tshaj plaws rau cov lus programming hu ua Lambda Expressions, ib hom lus tshiab uas tso cai rau cov neeg siv los sau cov haujlwm hauv zos raws li kev sib cav.
Raws li txoj cai, Java 1.8 puas zoo ib yam li 8?
Hauv JDK 8 thiab JRE 8 , cov hlua version yog 1.8 thiab 1.8 . 0. Nov yog qee qhov piv txwv uas siv txoj hlua version: java ua -version (ntawm lwm cov ntaub ntawv, rov qab java ua version 1.8.
Ib tug kuj yuav nug, puas yog JDK 8 rov qab sib xws? Java versions yuav tsum yog binary rov qab - sib haum . Piv txwv li, JDK 8 tuaj yeem khiav code compiled los ntawm JDK 7 lub JDK 6. Nws yog ib qho uas pom cov ntawv thov siv qhov no rov qab compatibility los ntawm kev siv cov khoom tsim los ntawm qhov sib txawv Java version.
Raws li, Java 1.7 puas zoo ib yam li Java 7?
txhua txoj kev mus 1.7 , kuj hu ua Java 7 ) feem ntau muaj kev txhim kho rau ob qho tib si JVM thiab tus qauv tsev qiv ntawv, yog li ob feem ntau yuav tsum tau khiav ua ke, thiab tau ntim ua ke hauv JRE. Yog tias koj khiav ib qho Java program hauv koj lub computer, koj muaj ib tug JRE ntsia. JDK yog Java Cov khoom siv txhim kho.
Lub npe code ntawm Java 8 yog dab tsi?
J2SE Code npe
| VERSION | CODE NPE | TSEEM CEEB |
|---|---|---|
| JDK 1.1.8 | Chelsea | Lub Plaub Hlis 8, 1999 |
| J2SE 1.2 | Chaw ua si | Peb Hlis 4, 1998 |
| J2SE 1.2.1 | (tsis muaj) | Peb Hlis 30, 1999 |
| J2SE 1.2.2 | Cricket | Lub Xya Hli 8, 1999 |
Pom zoo:
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