Java Syntax

Java is an object-oriented programming language which is known for its simplicity, portability, and robustness. The syntax of Java programming language is very closely aligned with C and C++ which makes it easier to understand. Let’s understand the Syntax and Structure of Java Programs with a basic “Hello World” program.

The main Method

The main() method is required and you will see it in every Java program:

public static void main(String[] args)

Any code inside the main() method will be executed. Don't worry about the keywords before and after it. You will get to know them bit by bit while reading this tutorial.

For now, just remember that every Java program has a class name which must match the filename, and that every program must contain the main() method.

System.out.println()

Inside the main() method, we can use the println() method to print a line of text to the screen:

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

Note: The curly braces {} marks the beginning and the end of a block of code.

System is a built-in Java class that contains useful members, such as out, which is short for "output". The println() method, short for "print line", is used to print a value to the screen (or a file).

Don't worry too much about how System, out and println() works. Just know that you need them together to print stuff to the screen.

You should also note that each code statement must end with a semicolon (;).