Deep dive into first java code

Public class MyFirstCode {             publicstaticvoid main(String[] args) {                         System.out.println("Hello World");             } }

Save as	MyFirstCode.java
Compile (on cmd prompt)	javac MyFirstCode.java
Run (on cmd prompt)	java MyFirstCode

Do you know

It is convention that file name should be same as name of class having main() method. But file can be saved by other name if class is not public. For Example,

class MyFirstCode {             publicstaticvoid main(String[] args) {                         System.out.println("Hello World");             } }

Save as	SecondClass.java
Compile (on cmd prompt)	javac SecondClass.java
Run (on cmd prompt)	java MyFirstCode

Program description:

·        Class : This keyword is used to declare class.

·        Public : This is one of the access specifier which means visible to all.

·      Static : Keep in mind, wherever static keyword comes that method or variable does not belong to any object. It has class level scope.

·        Void : Void is return type of method. This means it returns nothing.

·        String[] args : This is for storing command line arguments. Instead of String args[] one can use var-args as main(String… args).

·        System.out.println() : This is for printing text on console on new line.

Do you know : System.out.println()

·        System is a class in the java.lang package. ·        out is a static member of the System class, and is an instance of java.io.PrintStream. ·        println() is a method of java.io.PrintStream. This method is overloaded to print message to output destination, which is typically a console or file.