In our last chapter, we have seen the hello world program. Again let's create a simple hello world program and understand line by line. 



Now I am creating a new file JavaApplication in the filename must match the class name JavaApplication And put the following code


JavaApplication.java

public class JavaApplication {

    public static void main(String[] args) {
 
        System.out.println("Hello World!");
    }

}

Output:

Hello World!


The things you need to remember

  • Class Names − For all class names, the first letter should be in Upper Case. 
  • Method Names − All method names should start with a Lower Case letter. 
  • File Name − The name of the program file should exactly match the class name.



Example explained

Java is all about class and methods, in Our example, We named the class JavaApplication. A Class always starts with an uppercase first letter.


Note: Java is case-sensitive: "JavaApplication" and "aavaApplication" is different .


The main() Method

Just learn that every Java program has a class name that must match the filename and that every program must contain the main() method.



System.out.println()

It is used to print text on a console. We can use inside any methods to print text.



Java Modifiers

We can protect our methods and class by using an access modifier See the example above how I have used it.


  • Access Modifiers − default, public , protected, private
  • Non-access Modifiers − final, abstract, strictfp


I hope above the Useful information will help you to understand the Java basic program