Java Hello world Tutorial

 

Video Lecture

Hello world Program

public class Main
{
 public static void main(String[] args)
 {
  System.out.println("Hello world");
 }
}

Important points

• Every line of code must be inside a class. 
•  we named class Main.
•  A class must start with an uppercase first letter.
•  Java is case-sensitive: "MyClass" and "myclass" contain different meaning.

OUTPUT

Hello world

 

public class Application

• In java class name will be same as a file name.
• The name of file which is also the class name contain first letter capital
• Every single line of code written in the class in this called Application

public static void main(String[] args)

• Public : This is access modifier due to java can execute method at run time
• Static  :  Java virtual machine(JVM) load class in memory and call method
• void    : Method does not return any thing.
• String[] args : Method take only one argument as a string.

System.out.println();

System : It defined final class which is java.lang.package
out : It is like a print stream . which is also member of System class
println() : It print any argument passed to it.