Java (tsis yuav tsum tsis meej pem nrog Javascript) yog ib hom lus programming nrov tshaj plaws. Java yog hom lus programming qib siab uas tuaj yeem siv los tsim cov apps rau ntau lub tshuab ua haujlwm, suav nrog Windows, macOS, Linux, thiab Android. Txoj kev Java ua haujlwm yog koj rub Java Java Development Kit (JDK), uas yog siv los tsim Java code. Tom qab ntawv tus lej raug suav ua bytecode uas lub khoos phis tawj tuaj yeem nkag siab siv Java Runtime Environment (JRE). Nrog Java, koj tuaj yeem tsim cov apps rau ntau lub tshuab ua haujlwm nrog kev ua haujlwm tsawg. Qhov wikiHow no qhia koj cov hauv paus ntawm yuav pib li cas nrog Java.
Cov kauj ruam
Txoj Kev 1 ntawm 2: Txhim Kho Yam Koj Xav Tau
Kauj Ruam 1. Rub tawm thiab teeb tsa Java Runtime Environment
Java Runtime Environment yog txheej txheej software uas tau siv los khiav Java daim ntawv thov. Nws muaj cov tsev qiv ntawv, Java Virtual Machine (JVM), thiab lwm yam khoom siv xav tau los khiav Java daim ntawv thov. Tej zaum koj twb tau teeb tsa nws. Yog tias tsis yog, siv cov theem hauv qab no txhawm rau rub tawm thiab teeb tsa qhov tseeb version ntawm Java Runtime Environment ntawm koj lub computer:
- Mus rau https://www.java.com/en/download/ hauv web browser.
- Nyem Rub tawm Java.
- Nyem Pom zoo thiab pib rub tawm dawb.
- Qhib cov ntaub ntawv teeb tsa hauv koj lub vev xaib lossis Downloads nplaub tshev.
- Ua raws li cov lus qhia kom ua tiav kev teeb tsa.
Kauj Ruam 2. Rub tawm thiab teeb tsa Java Development Kit
Thaum Java Runtime Environment muaj cov software xav tau los khiav Java daim ntawv thov hauv koj lub khoos phis tawj, nws tsis muaj cov cuab yeej xav tau los sau thiab suav Java cov lej rau hauv Java chav kawm thov. Txog qhov ntawd, koj yuav xav tau Java Cov Khoom Txhim Kho. Siv cov theem hauv qab no txhawm rau rub tawm thiab teeb tsa Java Cov Khoom Siv Txhim Kho:
- Mus rau https://www.oracle.com/java/technologies/javase-downloads.html hauv web browser.
- Nyem Download tau JDK hauv qab qhov hloov tshiab kawg ntawm Java Kev Txhim Kho Khoom Siv.
- Scroll cia thiab nyem lub npe cov ntaub ntawv uas tsim nyog rau koj lub operating system (piv txwv li Windows Installer, macOS installer)
- Qhib cov ntawv rub tawm rub tawm hauv koj lub vev xaib lossis rub tawm cov ntawv tais ceev tseg.
- Ua raws li cov lus qhia kom ua tiav kev teeb tsa.
Kauj Ruam 3. Rub tawm thiab teeb tsa Java IDE
IDE sawv cev rau Kev Txhim Kho Ib Leeg Ib puag ncig. Cov no yog cov phiaj xwm koj tuaj yeem siv los sau, debug, thiab suav cov lej. Ob qhov feem ntau IDEs yog dab noj hnub thiab Netbeans. Koj kuj tseem tuaj yeem siv Android Studio los tsim cov apps rau Android khoom siv hauv Java. Siv ib ntawm kab hauv qab no txhawm rau rub tawm teeb tsa IDE rau Java.
- Dab noj hnub
- Netbeans
- Hauv Studio
Txoj Kev 2 ntawm 2: Tsim "Hello World" Program hauv Java
Kauj Ruam 1. Qhib koj Java IDE
Qhib qhov twg IDE koj xaiv los rub tawm. Koj tuaj yeem qhib cov apps hauv Windows Start menu, lossis Applications folder ntawm Mac.
Kauj Ruam 2. Tsim qhov tshiab Java project
Tej zaum koj yuav raug xaiv los tsim qhov haujlwm tshiab thaum koj xub qhib koj li IDE. Yog tsis yog, nyem Cov ntaub ntawv hauv cov ntawv qhia zaub mov saum toj kawg nkaus, thiab tom qab ntawd nyem qhov kev xaiv los tsim qhov haujlwm Java tshiab lossis daim ntawv thov java tshiab.
Kauj Ruam 3. Muab koj lub npe rau npe
Thaum koj tsim daim ntawv thov Java tshiab lossis phiaj xwm, tom qab ntawd koj yuav raug nug kom muab koj lub npe lub npe. Siv daim teb nyob rau sab saum toj kom ntaus lub npe rau koj qhov project. Koj tuaj yeem sau nws qee yam xws li "Nyob Zoo" lossis "Hello_World" lossis txhua yam uas koj xav tau.
Kauj Ruam 4. Tsim chav Java tshiab
Thaum koj tsim txoj haujlwm tshiab hauv koj li IDE, nrhiav lub pob Explorer Explorer vaj huam sib luag, uas feem ntau nyob rau sab laug. Nov yog qhov uas koj tuaj yeem pom txhua cov ntaub ntawv cuam tshuam nrog koj txoj haujlwm. Txhawm rau tsim chav kawm tshiab rau koj txoj haujlwm, nyem rau ntawm koj lub npe project thiab nyem rau Hoob tshiab lossis nyem Tshiab ua raws los ntawm Hoob. Ntaus lub npe rau chav kawm hauv "Npe" teb thiab nyem rau Tiav.
- Chav kawm Java zoo li tus tsim lossis qauv rau Java cov khoom. Ib chav kawm java tuaj yeem muaj ib lossis ntau yam khoom nrog lawv tus kheej cov khoom tshwj xeeb hu ua "Cov tswv cuab".
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Cov cai los tsim chav kawm tshiab zoo ib yam li
public class Nyob zoo {
- . Lo lus tseem ceeb "pej xeem" yog kev hloov kho nkag mus. Qhov no qhia qhia qhov uas tuaj yeem nkag mus rau chav kawm lossis yam khoom hauv qhov program. Lo lus tseem ceeb "chav kawm" qhia tias qhov no yog chav kawm tshiab. Lawv lo lus tseem ceeb "Nyob Zoo" yog lub npe ntawm chav kawm. Thaum kawg, qhov nkhaus-bracket "{" thaum kawg qhib chav kawm. Tej zaum koj yuav pom qhov kaw kaw-bracket "}" ob peb kab hauv qab. Txhua tus lej uas yog ib feem ntawm chav kawm no mus nyob nruab nrab ntawm ob kab ntawv nkhaus.
Kauj Ruam 5. Indent kab tom ntej thiab ntaus cov pej xeem zoo li qub tsis muaj qhov tseem ceeb (Txoj hlua args) {hauv kab tom ntej
Cov kab no yog siv los tsim cov tswv cuab tshiab. Tus tswv cuab yog tus yam ntxwv ntawm chav kawm. Ib tug tswv cuab uas muaj cov cai nrog cov lus qhia tshwj xeeb hu ua "method". Cov txheej txheem tuaj yeem raug hu thiab khiav ntawm cov xwm txheej tom qab hauv cov cai. Txhua qhov kev pabcuam Java yuav tsum muaj txheej txheem hu ua "main". Qhov no qhia qhov pib qhov haujlwm. Lo lus tseem ceeb "Pej Xeem" yog kev hloov kho nkag mus.
- Lo lus tseem ceeb "pej xeem" dua yog kev nkag mus hloov kho. Txij li nws tau teeb tsa rau "pej xeem" qhov no txhais tau tias txoj hauv kev no tuaj yeem raug hu nyob txhua qhov chaw hauv txoj haujlwm. Yog tias nws tau teeb tsa "ntiag tug", qhov no yuav txhais tau tias txoj hauv kev tsuas tuaj yeem nkag mus tau hauv chav kawm.
- Lo lus tseem ceeb "zoo li qub" qhia tias tus tswv cuab no tuaj yeem nkag mus ua ntej lwm yam khoom hauv chav kawm thiab tsis hais txog lwm yam khoom lossis lub sijhawm.
- Lo lus tseem ceeb "tsis muaj dab tsi" yog tus nqi rov qab los ntawm txoj kev. Qhov no qhia tias nws tsis rov qab muaj nuj nqis. Yog tias nws yuav rov qab tus lej, qhov yuav raug hloov mus rau "int" lossis "ntab" lossis "ob npaug", nyob ntawm seb hom kev muaj txiaj ntsig koj xav rov qab los.
- Lo lus tseem ceeb "tseem ceeb" tsuas yog lub npe ntawm tus tswv cuab. Txhua qhov kev pabcuam Java yuav tsum muaj txheej txheem hu ua "main" los qhia qhov pib qhov haujlwm.
Thaum twg los xij koj muaj cov ntawv nyob nruab nrab ntawm kab lus (piv txwv li Txoj hlua sib cav {}), nws hu ua kev sib cav. Kev sib cav tuaj yeem yog ntau yam xws li tus lej, ob npaug, ntab lossis hlua. Kab ntawv ntawm txoj cai no tau qhia tias txoj hauv kev yog kev cia siab tias yuav muaj kev sib cav ntawm hom array (cov npe khoom) uas muaj cov hlua.
Indenting thaum koj cov cai tsis tas yuav tsum tau ua, tab sis nws pab khaws koj cov cai kom zoo thiab qhia tias cov kab ntawv twg yog ib feem ntawm chav kawm twg, koom nrog, lossis txoj hauv kev. Indent txhua kab ntawm cov cai txhua lub sijhawm koj tsim chav kawm tshiab, tus tswv cuab, lossis txoj hauv kev. Los yog tom qab txhua qhov piv txwv ntawm qhov tshiab curly-bracket
Kauj Ruam 6. Indent kab tom ntej thiab ntaus System.out.println ("Nyob Zoo Ntiaj Teb");
Kab ntawv no yog siv los luam cov lus "Nyob Zoo Ntiaj Teb" ua ib txoj hlua.
- Lo lus tseem ceeb "System" qhia tias qhov no yog ib feem ntawm System chav kawm.
- Lo lus tseem ceeb "tawm" qhia tias qhov no yog qhov tso tawm.
- Lo lus tseem ceeb "printlin" qhia qhov program kom luam tawm qee yam hauv cov vaj huam sib luag tso tawm, lub davhlau ya nyob twg, lossis kab hais kom ua.
- Txij li thaum "Nyob Zoo Ntiaj Teb" nyob hauv kab lus, qhov no yog piv txwv ntawm kev sib cav. Hauv qhov no, kev sib cav yog txoj hlua uas hais tias "Nyob Zoo Ntiaj Teb".
Kauj Ruam 7. Kuaj koj qhov program
Kuaj hauv ib feem tseem ceeb ntawm lub cajmeem. Nov yog qhov koj ua kom ntseeg tau tias koj qhov program ua haujlwm tau zoo. Txhawm rau sim hauv Eclipse lossis Netbeans, tsuas yog nyem qhov ntsuab 'Ua Si' daim duab peb sab nyob rau sab saum toj ntawm lub vijtsam. Koj yuav tsum pom nws hais "Nyob Zoo Ntiaj Teb" hauv lub vaj huam sib luag tso tawm hauv qab ntawm lub vijtsam. Yog tias nws tsis yog, koj yuav tsum tau ua qee qhov kev daws teeb meem los kho qhov teeb meem. Koj tag nrho cov cai yuav tsum zoo li qhov no:
pej xeem chav MyProgram {pej xeem zoo li qub tsis muaj dab tsi tseem ceeb (Txoj hlua args) {System.out.println ("Nyob Zoo Ntiaj Teb"); }}
- Txheeb cov syntax rau txhua txoj cai thiab xyuas kom nws nkag mus tau zoo. Xyuas kom cov ntsiab lus tseem ceeb raug thiab sau kom raug, suav nrog cov peev txheej.
- Nco ntsoov tias txhua qhov qhib curly-bracket rau txhua chav kawm thiab cov txheej txheem muaj qhov sib xws kaw kaw-bracket tom qab tus txheej txheem lossis chav kawm.
- Google txhua qhov lus yuam kev koj tau txais thiab pom yog tias muaj kev kho. Qee zaum nws yuav muaj teeb meem nrog lub kaw lus. Tej zaum koj yuav xav rho tawm ib daim ntawv, lossis tseem rov nruab Java.
Yees duab - Los ntawm kev siv qhov kev pabcuam no, qee cov ntaub ntawv yuav raug muab qhia rau YouTube
Lub tswv yim
- Khaws koj cov cai tsim thiab ntxiv ntau cov lus rau nyeem yooj yim, rov nco, thiab hloov kho tshiab.
- Tom qab koj tau txais qee qhov kev paub, sim kom tau txais daim ntawv pov thawj programmer los ntawm Sun Microsystems nws tus kheej. Qhov no yog qhov hnyav dua li lwm yam ntawv pov thawj uas koj tuaj yeem tau txais los ntawm cov neeg thib peb.
- Kawm paub thev naus laus zis uas Java muaj zog: kev sib tham hauv network, kev sib txuas database, kev txhim kho web, thiab lwm yam.
- Tsis txhob siv "lej lej" yog tias koj tuaj yeem pab nws. Cov lej lej yog cov lej thiab tus nqi uas tau faib los ntawm koj cov cai thaum lawv yuav tsum tau txhais raws li qhov sib txawv, yog li lawv tuaj yeem rov siv tau, thiab piav qhia hauv kev tawm lus yog li lawv sawv cev tuaj yeem nkag siab. Qhov no ua rau cov cai yooj yim los tswj thiab hloov kho.
- Tsis tas yuav siv txoj hauv kev ntev (Java lub npe rau subroutines/kev ua haujlwm) tau saib qis txij li lawv ua rau koj cov lej nyuaj rau nyeem thiab hloov kho nyuaj. Kawm paub txheeb koj cov lej rau hauv cov qauv me me, meej uas ua ib yam zoo.
- Tom qab koj paub qhov pib, sim koom nrog qhov haujlwm qhib uas twb muaj lawm thiab ua haujlwm nrog lwm tus neeg. Los ntawm qhov pom ntawm kev kawm, qhov no muaj txiaj ntsig ntau dua los tsim qee yam loj thiab nyuaj ntawm koj tus kheej.
- Mus los ntawm API qhov muab nrog SDK. Ua tus cwj pwm ntawm kev nyeem cov lus piav qhia ntawm cov txheej txheem thiab chav kawm. Qhov no yuav pab koj nco qab txoj hauv kev lossis chav kawm siv lub sijhawm tom ntej koj xav tau.
- Master JUnit thiab sau cov ntawv xeem tsis siv neeg uas txheeb xyuas qhov sib xws ntawm koj qhov haujlwm. Cov haujlwm loj tshaj plaws ua qhov no.
- Sim sim koj li Java program hauv lub davhlau ya nyob twg lossis kab hais kom ua. Qhib lub davhlau ya nyob twg ntawm Mac, lossis CMD ntawm Windows. Ntaus "cd" ua raws li txoj hauv kev ntawm koj cov ntaub ntawv Java. Tom qab ntawv ntaus "java" ua raws koj lub npe program thiab nias Enter.
- Tsis txhob rov kho lub log. Java ib txwm hais txog kev rov qhib cov tsev qiv ntawv qhib. Yog tias koj xav tau qee yam uas tsis nquag siv, feem ntau yog lub tsev qiv ntawv uas pab koj
- Ua kom zoo dua ntawm qhov kev xav-ua qauv txheej txheem. Kawm paub yuav siv qhov qub txeeg qub teg, chav kawm, ntau yam sib txawv thiab kev kaw lus kom nce qib ntawm koj li kev cai. Ua lub hom phiaj-taw qhia yog ib qho ntawm Java cov ntsiab lus muaj zog, yog li siv nws tag nrho.
- Bookboon muaj qee phau ntawv pub dawb zoo ntawm Java rau cov pib tshiab
