Yadda Java ke Aiki da Fahimtar Tsarin Code na Java - Kashi na 2


A cikin sakonmu na ƙarshe 'Mene ne Java da Tarihin Java' mun rufe Menene Java, fasali na Java cikin cikakkun bayanai, tarihin saki da sunansa da wuraren da ake amfani da Java.

Anan a cikin wannan sakon za mu ci gaba ta hanyar aiki da tsarin code na Java Programming Language. Kafin mu ci gaba bari in tunatar da ku cewa an ƙirƙiri Java ne a hankali Rubuta Sau ɗaya Gudu Ko'ina/Kowane Lokaci (WORA) yana nufin tabbatar da cewa aikace-aikacen da aka haɓaka ya zama tsaka tsaki na tsarin gine-gine, Platform Independent kuma mai ɗaukar hoto.

Aikin Java

Tuna da waɗannan manufofin Java an ƙera shi tare da ƙirar aiki na ƙasa wanda za'a iya rarraba shi zuwa matakai huɗu.

Rubuta fayil ɗin tushen. Wannan fayil ɗin ya ƙunshi duk hanya, hanya, aji da abubuwa a cikin ƙaƙƙarfan ƙa'idar don Harshen Shirye-shiryen Java. Sunan fayil ɗin tushe yakamata ya zama sunan ajin ko akasin haka. Dole ne sunan tushen tushen fayil ɗin ya sami tsawo .java. Hakanan sunan fayil da sunan aji suna da mahimmanci.

Gudun fayil ɗin lambar tushen Java ta hanyar Java Compiler. Lambar Tushen Java Mai tarawa yana bincika kuskure da daidaitawa a cikin fayil ɗin tushe. Ba zai ƙyale ka tattara lambar tushe ba tare da gamsar da mai tara Java ta hanyar gyara duk kurakurai da faɗakarwa ba.

Mai tarawa yana ƙirƙira aji. Waɗannan rukunin fayil ɗin suna gaji iri ɗaya da sunan fayil ɗin lambar tushe, amma tsawo ya bambanta. Sunan fayil ɗin Tushen yana da tsawo filename.java, inda a matsayin tsawaita nau'in fayil ɗin da mai tarawa ya ƙirƙira shine filename.class. An ɗora wannan aji a cikin bytecode - bytecodes kamar sihiri ne.

Wannan babban fayil ɗin da Java Compiler ya ƙirƙira abu ne mai ɗaukar hoto kuma tsaka tsaki ne a tsarin gine-gine. Kuna iya shigar da wannan babban fayil ɗin don aiki akan kowane tsarin gine-gine da Platform/na'ura. Duk abin da kuke buƙata shine Injin Virtual Java (JVM) don gudanar da wannan lambar ko ta ina.

Yanzu ku fahimci matakai huɗu na sama ta amfani da misali. Anan ga ƙaramin samfurin lambar shirin Java. Kada ku damu idan ba ku fahimci lambar da ke ƙasa ba. Kamar yadda yanzu kawai fahimci yadda yake aiki.

public class MyFirstProgram
{
    public static void main(String[] args)
    {
        System.out.println("Hello Tecmint, This is my first Java Program");
    }
}

1. Na rubuta wannan shirin kuma na ayyana sunan aji MyFirstProgram. Yana da mahimmanci a lura cewa dole ne a adana wannan shirin azaman MyFirstProgram.java.

Tuna mataki na 1 a sama - Sunan aji da sunan fayil dole ne su kasance iri ɗaya kuma sunan fayil dole ne ya sami tsawo .java. Hakanan java yana da mahimmanci don haka idan sunan ajinku shine 'MyFirstProgram', sunan fayil ɗin tushen ku dole ne ya zama'MyFirstProgram.java'.

Ba za ku iya sanya masa suna 'Myfirstprogram.java' ko 'myfirstprogram.java' ko wani abu ba. Ta al'ada yana da kyau a sanya sunan ajin ku bisa ga abin da shirin yake yi a zahiri.

2. Don haɗa wannan fayil ɗin Source Java, kuna buƙatar wuce shi ta hanyar haɗin Java. Java compiler zai duba ainihin lambar tushe don kowane kuskure da faɗakarwa. Ba zai tattara lambar tushe ba har sai an warware duk matsalolin. Don haɗa lambar tushen java, kuna buƙatar gudu:

$ javac MyFirstProgram.java

Inda MyFirstProgram.java shine sunan fayil ɗin tushen.

3. A cikin nasara harhadawa za ku lura cewa Java compiler ya ƙirƙiri sabon fayil a cikin wannan directory sunan wanda shine MyFirstProgram.class.

Wannan fayil ɗin aji ana ƙididdige shi a cikin bytecodes kuma ana iya gudanar da shi akan kowane dandamali, kowane tsarin gine-ginen sarrafa kowane adadin lokaci. Kuna iya gudanar da fayil ɗin aji a cikin JVM (Java Virtual Machine) akan Linux ko kowane dandamali kamar:

$ java MyFirstProgram

Don haka duk abin da kuka koya a sama ana iya taƙaita shi kamar:

Java Source Code >> Compiler >> classfile/bytecode >> Various devices running JVM 

Fahimtar Tsarin Code a Java

1. Dole ne fayil ɗin lambar tushen Java ya ƙunshi ma'anar aji. Fayil Tushen Java ɗaya zai iya ƙunsar aji ɗaya kawai na jama'a/ajin babban matakin duk da haka yana iya ƙunsar yawancin aji masu zaman kansu/aji na ciki.

Ajin waje/mafi girman aji/aji na jama'a na iya samun dama ga duk aji mai zaman kansa/aji na ciki. Dole ne ajin ya kasance a cikin takalmin gyaran kafa. Duk abin da ke cikin Java abu ne kuma aji shine tsarin zane don abu.

Nunin demo na jama'a/masu zaman kansu a cikin Java:

public class class0
{
...
	private class1
	{
	…
	}

	private class 2
	{
	…
	}
...
}

2. Aji ya ƙunshi hanyoyi ɗaya ko fiye. Dole ne hanya ta shiga cikin takalmin gyaran kafa na ajin. Misali mai ban mamaki shine:

public class class0
{
	public static void main(String[] args)
	{
	…..
	…..
	}
}

3. Hanya ta ƙunshi bayani/umarni ɗaya ko fiye. Dole ne umarni(s) ya shiga cikin madaidaitan takalmin gyaran kafa na hanya. Misali mai ban mamaki shine:

public class class0
{
	public static void main(String[] args)
	{
	System.out.println("Hello Tecmint, This is my first Java Program");
	System.out.println("I am Loving Java");
	…
	...
	}
}

Hakanan yana da mahimmanci a ambata a wannan lokacin - Kowane Bayani dole ne ya ƙare da semicolon. Misali mai ban mamaki shine:

System.out.println("Hello Tecmint, This is my first Java Program");
...
...
System.out.println("I am Loving Java");

Rubuta Shirin Java na farko tare da cikakken bayanin. Ana sanya bayanin azaman sharhi anan (// na nufin an yi sharhi) a cikin wannan misalin. Ya kamata ku rubuta sharhi a cikin shirin.

Ba wai kawai saboda wannan al'ada ce mai kyau ba har ma saboda yana sa lambar za ta iya karanta ab ku ko wani a kowane lokaci daga baya.

// Declare a Public class and name it anything but remember the class name and file name must be same, say class name is MyProg and hence file name must be MyProg.java
public class MyProg

// Remember everything goes into curly braces of class?
{
 

// This is a method which is inside the curly braces of class.
   public static void main(String[] args)

    // Everything inside a method goes into curly braces	
    {
        
    // Statement or Instruction inside method. Note it ends with a semicolon
    System.out.println("I didn't knew JAVA was so much fun filled");
    
    // closing braces of method
    }

// closing braces of class
}

Cikakken bayanin fasaha na shirin Java mai sauƙi na sama.

public class MyProg

Anan a cikin sunan da ke sama shine MyProg kuma MyProg shine ajin Jama'a wanda ke nufin kowa zai iya shiga.

public static void main(String[] args)

Anan hanyar sunan shine babban wanda shine hanyar jama'a, yana nufin kowa zai iya shiga. Nau'in dawowa ba shi da komai wanda ke nufin babu ƙimar dawowa. Strings[] args yana nufin gardama na babbar hanyar ya kamata su kasance array wanda ake kira args. Kada ku damu da ma'anar 'tsaye' kamar yanzu. Za mu yi bayani dalla-dalla game da shi lokacin da ake buƙata.

System.out.println("I didn't knew JAVA was so much fun filled");

System.out.ln tambayi JVM don buga fitarwa zuwa daidaitaccen fitarwa wanda shine layin umarni na Linux a yanayinmu. Duk wani abu da ke tsakanin takalmin gyaran kafa na bayanin println yana samun bugawa yadda yake, sai dai idan ya kasance mai canzawa. Za mu shiga cikin cikakkun bayanai na masu canji daga baya. Bayanin yana ƙarewa da semicolon.

Ko da wani abu ba a bayyana ba a yanzu ba ka bukatar ka damu da wannan. Hakanan ba kwa buƙatar tunawa da komai. Kawai shiga cikin sakon kuma ku fahimci kalmomi kuma kuyi aiki koda lokacin da hoton bai bayyana sosai ba.

Shi ke nan a yanzu. Ci gaba da haɗi zuwa Tecment. Ka ba mu ra'ayin ku mai mahimmanci a cikin sharhin da ke ƙasa. Muna aiki a kashi na gaba \class da Babban Hanyar a Javakuma za a buga nan ba da jimawa ba.