Malangizo opanga pulogalamu ya Java yosavuta pa Unix
Zinthu Zazikulu Zokhudza Java
Java ndiyo njira yopangira opaleshoni yopanga mapulogalamu. Zimapangidwa ndi chinenero chokonzekera, mapulogalamu othandizira komanso malo othamanga. Pulogalamu ya Java ikhoza kukhazikitsidwa pa kompyuta imodzi ndikuyendetsa pa kompyuta ina iliyonse yomwe ili ndi nthawi yoyenera. Kawirikawiri, mapulogalamu akuluakulu a Java akhoza kuthamanga kumalo atsopano. Java imakhala yochuluka kwambiri moti ngakhale zovuta zambiri zolemba zingathe kulembedwa popanda kudalira machitidwe. Izi zimatchedwa Java% 100.
Ndi kukula kwa intaneti Java yatchuka popititsa patsogolo, chifukwa pamene mutsegula Webusaiti, mulibe njira yodziwira mtundu wa wogwiritsa ntchito. Ndi chinenero cha pulogalamu ya Java, mutha kugwiritsa ntchito "kulemba kamodzi, kuthamanga kulikonse" paradigm. Izi zikutanthauza kuti mukasonkhanitsa pulogalamu yanu ya Java, simungapange malangizo pazenera. M'malo mwake, mumapanga code Java byte, ndiko, malangizo a Java Virtual Machine (Java VM). Kwa ogwiritsa ntchito, ziribe kanthu kuti nsanja ikugwiritsa ntchito - Windows, Unix , MacOS, kapena osatsegula pa intaneti-malinga ngati ili ndi Java VM, imamvetsetsa zizindikirozo.
Mitundu itatu ya mapulogalamu a Java
- "Applet" ndi pulogalamu ya Java yokonzedwa kukhazikika pa tsamba la intaneti.
- "servlet" ndi pulogalamu ya Java yokonzedwa kuti ipangidwe pa seva.
Pazochitika ziwiri izi pulogalamu ya Java siingathe kuthamanga popanda ntchito za osatsegula pa Webusaiti ya applet kapena seva ya intaneti kwa servlet.
- "Java application" ndi pulogalamu ya Java yomwe ikhoza kuyendetsedwa yokha.
Malangizo otsatirawa ndiwomwe mukukonzekera kugwiritsa ntchito Java pogwiritsa ntchito kompyuta yanu.
Kufufuza
Chophweka kwambiri, mukufunikira zinthu ziwiri zokha kuti mulembe pulogalamu ya Java:
(1) Java 2 Platform, Standard Edition (J2SE), yomwe poyamba inkadziwika kuti Java Development Kit (JDK).
Tsitsani Linux yatsopano. Onetsetsani kuti mumasula SDK, osati JRE (i JRE ikuphatikizidwa mu SDK / J2SE).
(2) mkonzi wa malemba
Pafupifupi mkonzi aliyense amene mumapeza pa mapu a Unix adzachita (mwachitsanzo, Vi, Emacs, Pico). Tidzagwiritsa ntchito Pico monga chitsanzo.
Khwerero 1. Pangani Fayilo ya Chitsimikizo cha Java.
Fayilo yoyamba imakhala ndi malemba olembedwa m'chinenero cha pulogalamu ya Java. Mungagwiritse ntchito mndandanda uliwonse wa malemba kuti mupange ndi kusintha mafayilo oyamba.
Muli ndi njira ziwiri:
* Mungathe kupulumutsa fayilo ya FatCalories.java (kumapeto kwa nkhaniyi) pa kompyuta yanu. Njira iyi ingakupulumutseni mtundu wina. Ndiye, mukhoza kupita molunjika 2.
* Kapena, mukhoza kutsatira malangizo akutali:
(1) Bweretsani chipolopolo (nthawi zina amatchedwa terminal) window.
Pamene mwamsanga mutuluka, makalata anu omwe nthawi zambiri amapezeka amapezeka kunyumba kwanu. Mukhoza kusintha makalata anu pakalata yanu kunyumba nthawi iliyonse polemba cd pa nthawi yomweyo (makamaka "%") ndikukakamiza kubwerera.
Zopangira Java zomwe mumalenga ziyenera kusungidwa m'ndandanda yapadera. Mungathe kupanga zolemba pogwiritsa ntchito lamulo mkdir . Mwachitsanzo, kuti mupange chikalata cha java kunyumba yanu, mungayambe kusintha makalata anu panopa polemba lamulo ili:
% cd
Ndiye, mungalowetse lamulo lotsatira:
% mkdir java
Kuti musinthe makalata anu pakali pano, mukhoza kulowa: % cd java
Tsopano mukhoza kuyamba kupanga fayilo yanu yoyamba.
(2) Yambani mkonzi wa Pico mwa kujambula pico pamalopo ndikulimbikitsanso kubwerera. Ngati dongosolo likuyankha uthenga pico: lamulo silinapezeke , ndiye Pico sichipezeka. Fufuzani olamulira anu kuti mudziwe zambiri, kapena gwiritsani ntchito mkonzi wina.
Pamene muyamba Pico, idzawonetsa buffer yatsopano, yopanda kanthu. Ili ndilo malo omwe mudzasindikize code yanu.
(3) Lembani ndondomeko yomwe ili kumapeto kwa nkhani ino (pansi pa "Chitsanzo cha Java Program") mu buffer yopanda kanthu. Lembani chirichonse chimodzimodzi monga momwe zasonyezedwera. Wopanga Java ndi womasulira ndizovuta.
(4) Sungani codeyi polemba Ctrl-O. Mukawona Fayilo Dzina Kulemba :, mtundu wa FatCalories.java, kutsogolo kwazomwe mukufuna kuti fayilo ipite. Ngati mukufuna kupulumutsa FatCalories.java muzenera / kunyumba / smith / java, ndiye mungayese
/home/smith/java/FatCalories.java ndi makina obwereza .
Gwiritsani ntchito Ctrl-X kuti mutuluke Pico.
Gawo 2. Lembani Fayilo Yowonjezera.
Jalapala la Java, javac, limatulutsa fayilo yanu ndipo imamasulira malemba ake kuti Java JavaScript imvetsetse. Wogwiritsira ntchito amaika malemba awa kukhala fayilo ya khodi lachinsinsi.
Tsopano, tengerani tsamba lina la chipolopolo. Kuti muphatikize fayilo yanu yoyambira, sintha makalata anu pakali pano komwe fayilo yanu ili. Mwachitsanzo, ngati chitsimikizo chanu ndi / kunyumba / smith / java, mukhoza kufotokoza lamulo lotsatila pamalopo ndi kubwereza:
% cd / kunyumba / smith / java
Ngati mutalowa pwd mwamsanga, muyenera kuwona zolembera zamakono, zomwe mwachitsanzo ichi zasinthidwa kukhala / kunyumba / smith / java.
Ngati mutalowa mwamsanga, muyenera kuona fayilo yanu: FatCalories.java.
Tsopano mukhoza kusonkhanitsa. Pamsangamsanga, lembani lamulo lotsatirako ndipo dinani Bwererani: javac FatCalories.java
Ngati muwona uthenga wolakwika uwu:
javac: Lamulo silinapezeke
ndiye Unix sangapeze Java compiler, javac.
Nazi njira imodzi yodziwira Unix komwe mungapeze javac. Tiyerekeze kuti mwaika Java 2 Platform (J2SE) mu /usr/java/jdk1.4. Mukangoyamba, lembani lamulo lotsatila ndipo pindulitsani Kubwerera:
/usr/java/jdk1.4/javac FatCalories.java
Wopanga makina tsopano wapanga fayilo ya code byte Java: FatCalories.class.
Pamsangamsanga, mtundu ls kutsimikizira fayilo yatsopano ilipo.
Gawo 3. Kuthamanga Pulogalamu
Java VM imayendetsedwa ndi womasulira wotchedwa Java wotchedwa java. Wotanthauzira uyu amatenga fayilo yanu yachinsinsi ndipo amatsatira malangizo mwa kuwamasulira kuti makompyuta anu amvetse.
Mu bukhu lomwelo, lowetsani mwamsanga:
Java FatCalories
Mukamaliza pulogalamuyi muyenera kulowa manambala awiri pamene mawindo akuda a mzere wakuda akuwonekera. Pulogalamuyi iyenera kulembera nambala ziwirizo ndi chiwerengero chomwe chili ndi pulogalamuyi.
Mukalandira uthenga wolakwika:
Kupatula mu thread "yaikulu" java.lang.NoClassDefFoundError: FatCalories
Izi zikutanthawuza: java sangapeze fayilo yanu yachinsinsi, FatCalories.class.
Zimene mungachite: Malo amodzi a java amayesa kupeza fayilo yanu yamakina anu ndizomwe mukufuna. Mwachitsanzo, ngati fayilo yanu yachinsinsi ili mkati / kunyumba / smith / java, muyenera kusintha makalata anu pakali pano polemba lamulo lotsatira pa prompt and hit hit:
cd / kunyumba / smith / java
Ngati mutalowa pwd mwamsanga, muyenera kuwona / kunyumba / smith / java. Ngati mutalowa mwamsanga, muyenera kuona mafayilo anu a FatCalories.java ndi FatCalories.class. Tsopano lowetsani java FatCalories kachiwiri.
Ngati muli ndi mavuto, mungafunike kusintha kusintha kwanu kwa CLASSPATH. Kuti muwone ngati izi ndi zofunikira, yesani "kusokoneza" classpath ndi lamulo lotsatira:
samitsani CLASSPATH
Tsopano lowetsani java FatCalories kachiwiri. Ngati pulogalamuyi ikugwira ntchito tsopano, muyenera kusintha kusintha kwa CLASSPATH.